A healthy squash casserole recipe that is made with yellow squash, zucchini, a crunchy breadcrumb and Parmesan topping and then baked in the oven to crispy perfection! This easy baked casserole is a wonderful side dish recipe to serve up for summer picnics or at your Thanksgiving table!
Want other zucchini and summer squash recipes? You might also enjoy this Sauteed Zucchini and Squash, Oven-Roasted Vegetables, and these Zucchini Lasagna Roll-Ups.
Squash Casserole Recipe
Zucchini and yellow squash are some of the overlooked vegetables that somehow magically reappear during the summer months and at a Thanksgiving table.
I first discovered my love of cooking with this delightful combo when Cohl started coming home with enormous bags full of fresh summer produce from a fellow dentist at his office a few years ago.
After making a few batches of this Sauteed Zucchini and Squash, I started to run out of new recipe ideas.
Easy Baked Casserole
One week Cohl came home and the bag was packed to the brim with yellow summer squash and zucchini.
It would be a sin to let them all go bad, so I had to brainstorm a new summer recipe.
Squash casserole has always been one of my favorite summertime side dishes.
This time I wanted to try to make a healthier version that was still simple to make and baked in the oven.
Ingredients
Sure, the cheesy and cream-laden squash casseroles taste ah-maaazing, but let’s be real… all of that dairy takes away the incredible flavor of the fresh vegetables!
The ingredients for this recipe are pretty simple. You probably have most of them in your kitchen already:
- Zucchini and Yellow Summer Squash – Feel free to use all yellow squash or all zucchini if that happens to be what you have. However, I think the alternating colors are what make this casserole so unique and pretty!
- Olive oil – You can also use any other type of healthy oil you happen to have on hand that does not have a ton of flavor. Avocado oil, safflower, and sunflower oil will all work equally as well.
- Garlic Powder – The secret ingredient that gives this dish a unique flavor!
- Salt & Pepper – You can adjust these to your personal taste preferences.
- Parmesan cheese – Regular, dairy-filled, Parmesan cheese is my preference, but feel free to use a vegan and dairy-free Parmesan cheese, too.
- Panko Breadcrumbs – You can use regular breadcrumbs or gluten-free breadcrumbs. The taste will be minimally affected.
Cook’s Tip: Make sure you do not get a seasoned breadcrumb mixture as this will largely affect the taste of your casserole!
- Parsley – Not absolutely necessary but makes the casserole really pretty when serving.
How to Make
As I mentioned previously, this recipe is not only healthy, but it is also extremely easy to make.
Step-by-step Instruction:
- Preheat oven to 350 degrees.
- Prepare yellow squash and zucchini by cutting into 1/4-inch slices.
- You can either do this by carefully using a mandoline or with a sharp knife.
- Sprinkle 1/2 teaspoon salt over all of the slices and let sit for 10 minutes. Wipe away any excess moisture that forms with a paper towel.
- Layer the zucchini and yellow squash in a 9-inch square baking dish and sprinkle with remaining salt and pepper.
- Whisk together breadcrumbs, Parmesan cheese, and garlic powder. Sprinkle over zucchini and squash.
- Cover baking dish with aluminum foil and bake in preheated oven for 30 minutes. Broil for 3-5 minutes or until the topping becomes crispy.
Tip: Crispy Casserole Topping
Normally yellow squash and zucchini release A LOT of moisture when baked in the oven.
In order to let them release the majority of their moisture content BEFORE baking it in the oven, you will need to sprinkle a bit of salt over the prepared slices.
This simple step allows the sliced zucchini and squash to release a large amount of the water they retain and will help you to get a crispy, and not soggy!, casserole.
Prep-Ahead Tips
You totally can prep-ahead and have this side dish ready-to-go when you are. This is especially handy when it comes to preparing a healthy casserole for a backyard BBQ, picnic, or Thanksgiving day.
Prep-Ahead Steps:
- Prepare the recipe until it is time to bake it.
- Wrap the baking dish with aluminum foil and refrigerate up to 2 days until you are ready to eat.
- Let the casserole come to room temperature and pick up on the recipe where you left off!
Store & Reheat
Chances are you won’t have many leftovers at all of this summer squash recipe. But if you do, the best way to store it is in the pan you cooked it in OR you can place it in a tupperware container.
When ready to reheat, simply preheat your oven to 300 degrees, place it in a baking dish, and bake for 10-12 minutes or until heated through. You can also broil the casserole again for 1-2 minutes to bring back some of that crunchy topping.
Other Healthy Summer Squash Recipes:
Thai Zucchini Noodle Salad with Cabbage
Zucchini Lasagna Roll-Ups | Keto, Low-Carb
More healthy side dish recipes.
Healthy Summer Squash Casserole
Healthy Squash Casserole recipe that is made with yellow squash, zucchini, a crunchy breadcrumb and Parmesan topping and then baked in the oven to crispy perfection!
Ingredients
- 2 lbs. summer squash zucchini and yellow squash, cut into ¼-inch slices
- 2 ½ Tbsp. olive oil
- 1 ¼ tsp. salt divided
- ½ tsp. pepper
-
⅓
cup. Parmesan cheese* grated - ⅓ cup. Panko breadcrumbs gluten-free
- ¼ tsp. garlic powder
- 2 Tbsp fresh parsley finely chopped
Instructions
-
Preheat oven to 350 degrees.
-
Cut yellow squash and zucchini into thin, ¼-inch slices.
-
Sprinkle ½ teaspoon salt over the zucchini and squash slices. Let sit for 10 minutes and then dab to remove excess moisture with a paper towel.
-
Spray a 9-inch square baking dish with non-stick cooking spray.
-
Alternatively, overlap the zucchini and squash in a row. (See pictures.) You should be able to form 4 rows.**
-
Drizzle olive oil over the zucchini and squash and then sprinkle with salt and pepper.
-
In a small bowl combine Parmesan cheese, breadcrumbs, and garlic powder. Toss to combine and then sprinkle over the zucchini and squash.
-
Cover baking dish with aluminum foil and bake in preheated oven for 30 minutes.
-
Remove foil and turn heat to a High broil. Broil for an additional 5-7 minutes, or until breadcrumb topping starts to turn a golden brown.
-
Serve immediately with fresh parsley and enjoy!
Recipe Video
Recipe Notes
*Can use a vegan Parmesan cheese substitute.
**I like to get small-medium, similarly-sized summer squash so they will be able to fit into four rows easily!
DIANE TINNES says
How much garlic powder do you use? The recipe doesn’t include it in the ingredients.
London says
Hi Diane! So sorry for any confusion. The recipe has been updated with the amount of garlic powder you need 🙂 Thanks for asking!
Karen says
Can you do this in the air fryer
London says
You might be able to, but I have not personally tried it yet, Karen! Would love to know if you do and what you think!
Margaret E Clegg says
Love this recipe idea. With it being almost time to plant our garden, this will be perfect for the PLETHORA of zucchini we’ll have!
London says
It is the perfect thing to do with SO much squash and zucchini! Can’t wait to hear what you think, Margaret!
Judy says
Hi London , this recipe sounds delish , was wondering why the sodium content was so high in this recipe… Is there a way to cut back on the sodium, I’ll still make it & let everyone salt their own ….Thanks for the recipe !!
London says
Hi Judy! Parmesan cheese, breadcrumbs, and the added salt contribute to the somewhat high sodium count. You can definitely decrease the amount of salt added as well as look for a breadcrumb mixture that does not have as much sodium to help decrease it a bit. Would love to hear how it turns out for you!
Jules Shepard says
This recipe is actually on the menu for me this week along with some salmon! Can’t wait to give it a go!
London says
Yay!! Can’t wait to hear what you think, Jules!!
Donna says
This was a big hit at our Christmas Eve dinner! Thanks so much for the recipe!
London says
Yay!! So so happy you and the family enjoyed it, Donna!
Anonymous says
Very good! We’ll make it again 🙂
London says
Yay!! So happy you enjoyed it. Thanks for the comment and rating 🙂
Joyce says
Great flavor, too watery. I made it again but salted the squash slices, let them sit 5 minutes and squeezed them in paper towel. The end result was less watery and more like a casserole.
London says
That’s a great idea to dry them out a bit beforehand. I’ll have to try that next time! Thanks so much for your feedback, Joyce!
Mollie says
Loved this! Thanks for the great recipe!
London says
You’re so welcome, Mollie! So happy you enjoyed it 🙂
Lillian says
Loved this! The second time I made this I forgot the Parmesan cheese. Ugh. However I subbed with mozzarella and Italian breadcrumbs. Almost tasted like pizza…tried it a third time with tomato sauce. It was yum.
Thanks so much for the recipe! My entire family loves it.
London says
Hi Lillian! I absolutely love your idea to add tomato sauce… I bet that was delicious! Thanks so much for the comment 🙂
Savannah says
This looks absolutely delicious! I have to make this ahead of time and I was just wondering if I could go ahead and sprinkle the breadcrumbs and parmesan mixture over the zuchinni and squash and put it in the fridge or should I wait and sprinkle it after I take it out of the fridge and bring it room temperature? Thank you so much! 🙂
London says
Hi Savannah! Yes! You can go ahead and sprinkle the breadcrumbs/parmesan on top of the squash and refrigerate it. Bring the entire casserole to room temp before you bake it for the best results! Hope this helps 🙂