This Gluten Free Zucchini Squash and Corn Casserole is one of my favorite summer side dishes and I love making it when the garden is overflowing with zucchini and yellow squash and I need a recipe that uses a lot of it in the most delicious way possible. Fresh zucchini, yellow squash, sweet onion, garlic, and frozen sweet corn are stirred together with cheddar cheese, sour cream, and mayonnaise and baked under a golden gluten free bread crumb and parmesan topping that gets perfectly crispy in the oven.
Every bite is creamy, cheesy, and completely satisfying.
One of the best things about this casserole is that it is a crowd pleaser for everyone at the table regardless of whether they eat gluten free.
A reader made this for her gluten eating friends and said it was a big hit and a definite keeper. That kind of feedback is exactly why I love sharing this recipe.
It works beautifully as a summer potluck dish, a barbecue side, or just a special weeknight vegetable side dish when the garden is at its peak.
I also have recipes for Baked Kale and Zucchini Pilaf, Gluten Free Summer Squash Casserole and Gluten Free Zucchini Chocolate Chip Cookies that are all great options for your extra zucchini.
You can find all of my side dish recipes here: Gluten Free Side Dish Recipes
Instructions
Preheat your oven to 350 degrees.
In a large bowl stir together the yellow squash, zucchini, onion, garlic, corn, cheddar cheese, sour cream, mayonnaise, eggs, salt, pepper and 1 cup of gluten free bread crumbs.
Pour the squash mixture into a 9x13 baking dish or 3 quart baking dish.
Mix together 1 cup gluten free bread crumbs and melted butter. Sprinkle over the squash mixture in the baking dish. Top with finely grated parmesan cheese.
Bake at 350 degrees for 45 minutes. The topping will be slightly browned when the casserole is done.
Supplies
Frequently Asked Questions
Fresh zucchini should have a very soft skin that doesn't need to be peeled. If your zucchini has a hard skin it is likely old or over ripe. If possible, I would choose a different zucchini to cook with and compost the over ripe zucchini with tough skin.
Most of the nutrition is in the deep green skin of the zucchini squash, which makes it a great reason to leave the peel on.
Yes! You can assemble the entire casserole the night before including the bread crumb topping and store it covered in the refrigerator overnight. When you are ready to bake simply take it out of the refrigerator while the oven preheats and then bake as directed adding 5 to 10 extra minutes if the casserole is going in cold. This is a great option for potlucks and holiday dinners when you want to minimize day of cooking.
No and that is one of the things I love most about this recipe. Unlike my Gluten Free Summer Squash Casserole which requires sauteing the squash first this recipe goes directly into the baking dish without any stovetop cooking. The vegetables release their moisture as they bake and the eggs, sour cream, and mayonnaise help absorb that liquid and create a creamy and set casserole. If your zucchini is very large and watery you can salt the cubes lightly and let them drain in a colander for 15 minutes before mixing everything together.
Absolutely! If you do not have yellow squash or cannot find it just use all zucchini and the recipe works perfectly. The yellow squash adds beautiful color contrast to the casserole but the flavor and texture are nearly identical. You can also use all yellow squash if that is what you have on hand.
This casserole pairs beautifully with grilled chicken, BBQ ribs, pulled pork, grilled steak, or any summer main dish you can think of. It is hearty enough to hold its own as a vegetarian main dish as well served alongside a simple green salad. It is the perfect potluck and barbecue side dish because it feeds 8 people beautifully and travels well in the baking dish.
More Recipes You Might Enjoy
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Gluten Free Zucchini Squash and Corn Casserole
- Total Time: 1 hour
- Yield: 8 servings 1x
- Diet: Gluten Free
Description
This Gluten Free Zucchini Squash and Corn Casserole is a rich, creamy, and cheesy baked side dish loaded with fresh yellow squash, zucchini, sweet corn, garlic, and onion baked with cheddar cheese, sour cream, and mayonnaise under the most beautiful golden gluten free bread crumb and parmesan topping. It is hearty enough to steal the show at any summer dinner table and so delicious that even your non gluten free guests will come back for seconds. Naturally gluten free and perfect for summer barbecues, potlucks, and family dinners!
Ingredients
- 1 ½ pounds Yellow Squash, cut into ½-inch cubes
- 1 ½ pounds Zucchini, cut into ½-inch cubes
- 1 large Sweet Onion, chopped
- 2 Tbsp Minced Garlic
- 32 ounce bag Frozen Corn
- 2 cups Cheddar Cheese, shredded
- ½ cup Sour Cream
- ½ cup Mayonnaise
- 2 large Eggs, beaten
- 1 ½ tsp Sea Salt
- 1 tsp Coarse Ground Black Pepper
- 2 cups Gluten Free Bread Crumbs
- ¼ cup Unsalted Butter, melted
- ½ cup Parmesan Cheese, finely grated
Instructions
Preheat your oven to 350 degrees.
In a large bowl stir together the yellow squash, zucchini, onion, garlic, corn, cheddar cheese, sour cream, mayonnaise, eggs, salt, pepper and 1 cup of gluten free bread crumbs.
Pour the squash mixture into a 9x13 baking dish or 3 quart baking dish.
Mix together 1 cup gluten free bread crumbs and melted butter. Sprinkle over the squash mixture in the baking dish. Top with finely grated parmesan cheese.
Bake at 350 degrees for 45 minutes. The topping will be slightly browned when the casserole is done.
Notes
If you don't have yellow squash you can substitute with zucchini and just use zucchini in this recipe.
- Prep Time: 15 minutes
- Cook Time: 45 minutes
- Category: Side Dish, Vegetables
- Method: Baking
- Cuisine: American
If you made this Gluten Free Zucchini Squash and Corn Casserole I would love to hear what you thought! Please leave a star rating and a comment below. This is one of my favorite summer side dish recipes and I hope it becomes a staple in your kitchen too!
Storage
Store leftover gluten free zucchini squash and corn casserole covered in the refrigerator for up to 4 days. Reheat individual servings in the microwave covered with a damp paper towel in 30 second intervals until heated through or place the entire dish back in a 350 degree oven covered with foil for about 15 to 20 minutes until warmed through. Remove the foil for the last 5 minutes to crisp up the bread crumb topping. This casserole is not recommended for freezing as the sour cream and mayonnaise based filling does not hold up well to freezing and thawing.
Top Tip
This casserole does not require pre cooking the vegetables on the stovetop before baking unlike some squash casseroles. The zucchini and yellow squash release their moisture as they bake directly in the dish. However if your squash pieces are very large or very watery you can salt them lightly and let them sit in a colander for 15 to 20 minutes to draw out some of the excess moisture before mixing everything together.
This is especially helpful if you are using very large garden zucchini which tends to hold more water than smaller zucchini.
