This Easy Zucchini Au Gratin is a healthy baked casserole loaded with cheese! This gooey side dish is layered with cheddar, mozzarella, and Parmesan cheese for the perfect dose of flavor. Who says veggies can't be fun?
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Have you had my Instant Pot Scalloped Potatoes Au Gratin? Did you wish there was a version with fewer carbs? Well, this is it.
Table of Contents
The Difference Between Scalloped and Au Gratin
You usually hear these terms when referring to potatoes. Both of these are considered casserole like dishes and both are served with a creamy sauce. Scalloped potatoes do not use grated cheese, they are usually made with just heavy cream and milk.
A lot of au gratin recipes will use breadcrumbs for an even crisper topping! I love that method as well, but you can accomplish a similar result by broiling the dish to toast the cheese a little bit right before you pull it out of the oven.
You can read more about The Difference Between Scalloped and Au Gratin here.
How to Slice the Zucchini
My preference is to slice it into ¼ inch rounds using this mandolin from Amazon. ½ an inch thick will work as well.
How to Prevent Excess Water From the Zucchini
Zucchini is a very watery vegetable. Zucchini is 94% water. If you slice up the zucchini and add it to the dish without preparing it properly beforehand, you will end up with something that looks a lot like soup.
After you have sliced the zucchini arrange it on a flat surface with towels or paper towels. Sprinkle salt throughout and let it sit for at least 30 minutes. You will see moisture and water appear. Blot the excess and wring out any water you can.
Try to remove as much as you can. Since the veggie is mostly water, getting it all out isn't really possible, but it will help a ton. Another tip you can do, if your dish is too watery, is saute or grill the zucchini beforehand. It will add flavor and dry out the zucchini.
How to Make Zucchini Gratin
- Preheat oven to 400 degrees.
- Place the sliced zucchini on a flat surface with towels or paper towels. Sprinkle both sides of the zucchini with salt.
- Allow the zucchini to sit for 30 minutes.
- Heat a saucepan on medium-high heat and add butter.
- When melted, add garlic.
- Add in cream cheese, whipping cream, Parmesan reggiano, and shredded cheddar cheese. Add in onion powder, salt, and pepper to taste.
- Spray a 9x13 baking dish with cooking spray. Arrange the zucchini in rows throughout the dish. Drizzle the cheese sauce throughout.
- Sprinkle shredded cheddar and the mozzarella throughout the pan.
- Bake.
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How Long to Cook and Bake
I bake the dish uncovered for 30-35 minutes. If you like a crisp top, a couple of minutes before the dish has finished baking, turn on the Broil function on the oven. Broil for 1-3 minutes until the top has crisped.
What Type of Cheese to Use
I like to use a combination of cheddar, Parmesan Reggiano and mozzarella. You can use any cheese you wish. It's up to you. I purchase block cheese and grate it myself. Pre-shredded cheese typically has preservatives and corn starch. It does not melt as well. Keep this in mind if you choose not to make the dish using my method.
How to Store It and How Long It Will Last in the Fridge
You can store the dish tightly sealed and covered for 3-4 days.
Freezer Tips
You can freeze this dish, but note that when reheated, dairy separates. This does not typically impact the flavor, but it will impact the look.
Pair this with these Main Dishes
Keto Low Carb Smothered Pork Chops
Smothered Chicken
Air Fryer Cornish Hens
Air Fryer Whole Chicken
Air Fryer Steak
More Zucchini and Side Dish Recipes
Keto Low Carb Zucchini Shrimp Alfredo
Keto Low Carb Zucchini Bread
Air Fryer Zucchini Chips
Zucchini Lasagna Roll Ups
Zucchini Taco Boats
Zucchini Pasta Salad
Roasted Brussel Sprouts with Garlic
Broccoli Au Gratin
Easy Zucchini Au Gratin
Ingredients
- 3-4 whole fresh zucchini Sliced ¼-1/2 inch thick into slices. Unsliced, mine weighed 3 pounds.
- 1 tablespoon butter
- 2 garlic cloves minced
- ¼ cup heavy whipping cream
- 4 oz cream cheese
- 1 cup shredded cheddar cheese Divided into 2 servings.
- ¼ cup shredded parmesan reggiano cheese
- 1 teaspoon onion powder
- salt and pepper to taste
- ½ cup shredded mozzarella cheese
Instructions
- Preheat oven to 400 degrees.
- Place the sliced zucchini on a flat surface with towels or paper towels. Sprinkle both sides of the zucchini with salt.
- Allow the zucchini to sit for 30 minutes. This will sweat out the excess moisture of the zucchini. Skipping this step will result in a watery dish. After the 30 minutes. Blot and wring out any excess moisture.
- While the zucchini rests, prepare the filling for the dish. Heat a saucepan on medium heat and add the butter.
- When melted, add the garlic and cook for a couple of minutes until fragrant.
- Add in the cream cheese, whipping cream, Parmesan reggiano, and ½ cup shredded cheddar cheese. Stir. Add in the onion powder, salt, and pepper to taste. Taste the sauce repeatedly and adjust the flavor to taste as needed.
- Stir continuously until the cheese has melted.
- Remove from the heat and set aside.
- Arrange the zucchini in rows throughout a 9x13 baking dish. Drizzle the cheese sauce throughout.
- Sprinkle the remaining ½ cup of shredded cheddar and the mozzarella throughout the pan.
- Bake (uncovered) for 30-35 minutes until golden brown. If you like a crisp top, a couple of minutes before the dish has finished baking, turn on the Broil function on the oven. Broil for 1-3 minutes until the top has crisped.
- Cool before serving.
Video
Notes
- If you allowed the zucchini to rest and your dish is still too watery, saute or grill the zucchini beforehand. It will add flavor and dry out the zucchini.
- You can add Italian Seasoning (about 1 teaspoon) if you are looking for zest, or serving this with an Italian themed main dish.
- You can use any cheese you wish. It's up to you. I purchase block cheese and grate it myself. Pre-shredded cheese typically has preservatives and corn starch. It does not melt as well. Keep this in mind if you choose not to make the dish using my method.
- You can make this using shredded zucchini or zucchini noodles if you wish.
- You can reduce the amount of fat in the recipe by using low-fat cream cheese and cheese in the recipe. You can also lessen the amount of cheese used.
- This is not a dish I would prep and make ahead because it will alter the texture of the cheese and it will harden.
Tyler says
This recipe SLAPS I’m telling you what... potato who? I had high hopes for this recipe and it blew those out of the water. Going to be making this weekly!
staysnatched says
Yay! I'm so glad to hear that!
Sophia Lall says
The tips on how to properly prepare the zucchini are so helpful! I have tried to make a bunch of recipes that end up a soupy mess. This method of drying it removing the water before cooking works.
staysnatched says
Yay! I'm glad you found the tip worked.
Shauna says
Baked zucchini that isn’t watery!!!! Do NOT skip the step of letting the zucchini sit, I made sure to do it and the texture of the zucchini was perfect and the sauce stayed thick and creamy, no extra water! Will be making this again, only regret this time was making a half batch.
staysnatched says
YES! Make that full batch next time.
Julie S. says
This zucchini dish was delicious!! My whole family enjoyed it including my 2 and 5 year old. I will definitely be making this again!
staysnatched says
Yay! Glad to hear the kiddos liked it!
Nicole Siegel says
This dish was exactly what I was craving! The cheese sauce is so creamy and the zucchini melted in my mouth, it is everything comfort food is supposed to be! Definitely going to be a staple going forward!
staysnatched says
Glad to hear you can make it a staple!
Angela B says
So damn good! I didn't have cream cheese when I made this which means it can only get better. I can't wait to take this to Thanksgiving dinner!
staysnatched says
Yay! It definitely will! Enjoy.
Ann says
@staysnatched,
How much is a serving? A cup, half cup, etc?
staysnatched says
1/6th of the recipe. Feel free to use a measuring cup if you wish.
Jessica says
So good! I’m always looking for new ways to get more veggies in and this does not disappoint. Make this now!
staysnatched says
This is one of my favorite ways to use zucchini!
Melissa says
This was my first staysnatched recipe. The instructions were simple, to the point and tasted of cheesy goodness. I made it for my family and then again for a friend who had a baby (she asked for this recipe out of all the food I brought to her house). It was very easy to make ahead and have my friend bake at her house. A delicious way to use up all those summer zucchini from your garden.
staysnatched says
Thank you! I'm glad you found the recipe easy!
Isis Clark says
This zucchini au gratin is so good!!! It’s creamy, cheesy and made with love. I followed the recipe to the T! Brandi explained the instructions very well. I am very satisfied. Will definitely make this again. Thank you so much!
staysnatched says
Wonderful! This is such a great side dish.
Christina says
Loved this casserole!!!! It was delicious and my family loved it. The tip on drying out the zucchini was very helpful. This dish was tasty, not watery, and the crunchy cheesy topping made it one of my favorites.
staysnatched says
Yay! I'm so glad you enjoyed this.
Jennifer says
Another awesome recipe from Brandi! I was looking for something else to do with zucchini and this was great, so creamy and not watery (as long as you follow directions).
staysnatched says
Yes! The key is following the directions.
Sabrina Boucher says
These were really good! Great recipe to use when trying to switch up your veggie game a little.
staysnatched says
A new spin on veggies for sure!
hannah says
Really yummy cheese sauce... make sure to sweat out the zucchini as much as possible... everything else is a breeze
staysnatched says
Wonderful.
Hailey Graff says
Absolutely delicious! The sauce was surprisingly easy to make - mainly because you have to buy a block and shred your own cheese! Honestly, the best tip I’ve ever seen. The cheese crisped up on its own - which is probably due to my oven, but a bonus nonetheless. It was great the next morning, I reheated a piece in the microwave and scrambled eggs on top of it. Versatile and delicious!
staysnatched says
I love crisp cheese. Glad you enjoyed it!
Chris says
Amazing! The flavors, the process, the finished product! It was all great!! The whole family loved it!
staysnatched says
So glad to hear it!
India says
During quarantine, I honestly got tired of my own cooking. I seeked out bloggers that looked like they had great recipes and came across Brandi's page from another influencer. I've made a few of Brandis' recipes before and decided to make this one before my zucchini went bad. Boy was I happy!!! I LOVE zucchini so this was just what I needed. I paired with lamb chops and it was amazing!!! Go try this recipe!!!!
staysnatched says
Thanks for sharing!
Emily Clark says
This was SO fast to make, all ingredients I had on hand, and not a single spoonful was left over. Officially a new family favorite. Letting the Zucchini dry out definitely made a HUGE difference. I don’t think I’ll ever need to make the potato version again!
staysnatched says
So glad everyone enjoyed it.
Danica says
I’ve made this recipe so many times and it’s so good each time. It’s incredibly easy to make and damn delicious!
staysnatched says
Wonderful. I'm glad you enjoyed it.
Samantha says
This was SO GOOD! Don’t sleep on this recipe summer folks, zucchini is in season and cheap as heck! I followed the step with letting it rest salted and zero sogginess. I mean NONE. The cheese sauce was rich and creamy and the dish was decadent but guilt free. I love cooking with real food and Brandi never disappoints.
staysnatched says
Yes! Real good is the best.
Hannah says
This has been a staple in our house. We make it when friends and family visit and it’s always a hit! Super simple and comes out delicious every time.
staysnatched says
I'm so glad you enjoy it!
Caroline Gunn says
I love this dish. One of my favorite summertime side dishes. It is so flavorful and easy to make. Also love the info about shredding your own cheese, it truly does make a big difference.
staysnatched says
Yay! And you're right! Huge difference!
Kristen says
This recipe is SO good and the tips on drying out the zucchini first were very helpful. This also makes a huge portion which would make it perfect for dinner party. It was just me and the hubs though and I’m so excited to be having it with lunch this week!
staysnatched says
Perfect for lunch!
Nicole Braswell says
This recipe is a winner. It’s a wonderful way to use all the summer squash coming out of the garden this time of year and a delicious way to mix up the side dishes to weeknight meals. I thought I had reviews it before, but Brandi is pumping out the winners so it may have been something else she created that was also a hit in my home. Try this recipe. It does not disappoint!
staysnatched says
Thank you! I'm so glad you enjoyed it.
Julia McClure says
This was delicious!!! NO leftovers- that good!
staysnatched says
haha! that's always a good sign!
Jessica says
Love when there is no leftovers except when you want leftovers! I wanted leftovers...so delicious, so creamy and not watery at all! New favorite way to make zucchini!!
staysnatched says
haha I'm glad you enjoyed it.
Natalie says
Love this recipe. Delicious and Super easy. Do not skip the dehydration process lol! I forgot to use the butter it was still delicious.
staysnatched says
I'm so glad you enjoyed it!
Belinda says
Recipe is quick, clear, and easy to follow - but most importantly turned out delicious. It’s garlicky, creamy, and cheesy. Great new recipe to add to the rotation of veggie side dishes - my husband and kids loved it, too.
staysnatched says
I'm glad everyone loved it!
Kim says
Sounds great and have everything ready to go for company tomorrow. Can it be assembled ahead and baked just before serving or wouldn’t that be recommended?
staysnatched says
I don't typically do this with cheese dishes because it hardens the cheese.
Edie says
Made this tonight! So easy and yummy! Thanks for the recipe
staysnatched says
You're welcome! I'm glad you enjoyed it.
Judy Moore says
Just made again. Absolutely delicious. Recipe is perfect!
staysnatched says
Wonderful! Glad you enjoyed it.
Felicia says
This recipe is fire!!!
First of all the instructions are perfect. I prepped the zucchini just as Brandi mentioned. The dish had the perfect consistency. It was cheesy and I browned the top and it was just perfectly delicious! I heard the leftovers reheat amazingly. My husband, who made a face while I was prepping this, at half the pan. Definitely a winner and I’m going to be loaded up with zucchini once my veggies start growing. Thank you for this recipe!
Joanna says
Thank you so much for sharing this !! It was wonderful! I loved it!! Can’t wait for lunch tomorrow.
staysnatched says
So glad to hear it!
Typhanie says
Amazing!!! Kiddo ate it and asked for 2nds!
staysnatched says
So glad to hear it!
Victoria says
This is so yummy! Subbed the mozzarella for smoked Gouda because it’s what I had. This is a great alternative to potato au gratin. Can’t wait to eat the leftovers!
staysnatched says
I’m so glad you enjoyed it!
Lisanne says
ready to put in oven,???? can i refrigerate for a day or two before baking??? need time saver Thanks🦃
staysnatched says
I wouldn’t. The cheese will harden.
Diane says
Easy to make and very good.
Diane says
Loved it, easy to make and have leftovers
staysnatched says
Perfect for leftovers!
Anonymous says
We all use different name products so I redo my carbs, and all of it and sometimes come out with less of everything.
GBP says
Great recipe!!! Made many times. Easily varied with ingredients on hand. For example, had only one zucchini, so I alternated thinly sliced sweet potato and the zucchini in rows. Great! Didn't have milk or cream so I used chicken stock, WONDERFUL! Another, placed strips of red bell pepper across the top then added the final cheese, turned out great. Brilliant base recipe. Always works as long as you sweat those zucchini slices. THANKS!!! PS first time I used cream cheese as a base for a sauce. I now use cream cheese in many other sauces when I don't have time or patience to make a roux. This recipe inspires!
staysnatched says
I’m glad you enjoyed it!
Sarah S says
I layered zucchini and sweet potato to combine the two au gratins and it was incredible!!! I always appreciate the thorough recipe and tips. You never disappoint, Brandi!
staysnatched says
Thank you! So glad you enjoyed it!
Ikesha says
This was SOOO good!!! MY mistake was adding salt with my other seasonings, even though I had salted the zucchini during the resting process. But I'll just make a little extra sauce to help with that & the next time I won't add anymore.
staysnatched says
Nice! And yes, salting to taste is key.
Kalina says
MY NEW FAVORITE RECIPE! My fiance HATES zucchini. I made this for him and well... let's just say it's his new favorite recipe too! He ate two HUGE portions. I was so happy with this recipe. Very underrated! Everyone should give it a try!
staysnatched says
I'm so glad he enjoyed it!
Annabelle says
don't skip the zucchini prep.
I added some bread crumbs to the top while it baked, and omg. so. good. Definitely a great, lower cal alternative to potatoes, super yummy & hearty!!
staysnatched says
I love that idea!
Doreen says
I sautéed a sweet onion and used American cheese which browned nicely with out broiling in lieu of mozzarella. It was excellent not a drop left!!
staysnatched says
That sounds good!
Debra Kolodge says
The tangy, cheesy flavor of this casserole made a fantastic side dish to our meal. My husband is not even a huge zucchini fan, but loved it! Easy to prepare, and yummy. I'll be making again soon!
staysnatched says
Glad to hear you will make it again!
Teeda4 says
Can I substitute sour cream for the heavy cream? I don't have any heavy cream.
staysnatched says
Sure, if you want.
Jennifer says
Made this dish tonight and it was delicious!! Will definitely make again.
staysnatched says
So glad to hear it!
Barbara says
This is delicious. I had some left over corn so I put it on the bottom of the pan. Put the zucchini and the sauce in, put some tomatoes slices on top with a little cheese on then and then added French fried onions. It was the bomb!
staysnatched says
Sounds so good!
Diane says
looks wonderful; I plan on making this tonight! If I half this recipe (only have 2 zucchini and for 2 people), do I still bake for same amount of time? Thanks!
staysnatched says
I haven't tried that, but I would assume so. Keep a watchful eye.
Karen says
This was so good! Thank you for posting! I chose to sauté the zucchini and only modification was I used chopped green onions instead of onion power. Tasted just like my parents' potato recipe from days gone by. So good!!
staysnatched says
You're welcome!