Zucchini and squash casserole - easy, healthy and vegetarian! This one skillet wonder is a great recipe for meatless Monday (or any night of the week). Simply sauté diced veggies, add shredded cheddar cheese and seasonings, then bake for ten minutes. It's that simple!
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This tasty corn casserole typically serves as a main course in our home. It can also make the perfect summer side dish to go with almond crusted chicken, smoked chicken thighs, steak or any other grilled protein!
Ingredients & Substitutions
This simple recipe calls for just 13 ingredients and is packed full of healthy veggies!
- Extra virgin olive oil: for sautéing diced veggies.
- Fresh squash: I typically use zucchini, yellow squash and calabacita squash. If you can't find calabacita squash at the store, substitute an additional zucchini or yellow squash (or any other variety of summer squash).
- Shallots: shallots add delicious flavor to this dish! A small white or yellow onion will also work fine.
- Cauliflower rice: substitute cooked white or brown rice if you prefer.
- Black beans: delicious, velvety black beans add nice texture and lots of fiber.
- Sweet corn: I love using fresh corn but frozen will also work.
- Garlic, salt & black pepper: some simple spices (feel free to experiment).
- Cheese: freshly shredded yellow or white cheddar cheese.
- Fresh parsley: adds a bright flavor and visual appeal!
How To Make Squash And Corn Casserole
Keep scrolling for the complete recipe card and measurements. We'll start here with a quick rundown!
- First, preheat your oven to 400°F.
- Measure olive oil into a large, oven safe skillet and place on medium to medium-high heat.
- Dice zucchini & squash and add to the skillet. Sauté for 8-10 minutes.
- Dice shallots and mix into the skillet. Sauté for 2 more minutes.
- Add cauliflower rice, black beans, corn, half of your shredded cheese and spices. Gently mix everything together and then pat evenly into the skillet.
- Sprinkle remaining cheese on top of ingredients and bake for 10 minutes.
- Remove from the oven, top with fresh chopped parsley leaves and allow casserole to cool.
- Plate and enjoy!
Note: sometimes I enjoy adding a little bit of sour cream topping to my casserole, but that's totally optional!
- If you don't have an oven safe skillet, simply cook ingredients in a regular sauté pan and then pour mixture into a 13 x 9-inch baking dish before transferring to the oven. If you happen to have a Dutch oven - this will also work!
- For this recipe I use a 2 quart skillet (10 inches in diameter and 2 inches deep). Once all ingredients are added, the skillet is very full. Gently and carefully stir the ingredients together and they'll begin to cook down a bit, so the skillet won't be quite as full. You can also add cauliflower rice in shifts to help prevent overflow.
Step By Step Photos
More Healthy One Pot Meals
- One Skillet Chicken Thighs With Creamy Spinach Sauce
- Spinach & Blue Cheese Stuffed Chicken Breasts
- Delicious, Creamy Taco Soup
- Cauliflower Chickpea Curry
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Zucchini, Squash And Corn Casserole (One Skillet)
- Oven safe skillet (or dutch oven) *see note below
- 1 tablespoon extra virgin olive oil
- 1 medium zucchini
- 1 small yellow squash
- 2 small calabacita squash *or substitute additional zucchini/yellow squash or another variety of summer squash
- 2 shallots
- 4 cups cauliflower rice *see note below
- ½ cup black beans
- ½ cup sweet corn
- 1 teaspoon salt
- ½ teaspoon ground black pepper
- ½ teaspoon garlic powder
- 3 cups shredded sharp cheddar cheese *divided in half
- ¼ cup chopped parsley
- A little bit of sour cream topping is great on this casserole!
Recipe notes:Oven safe skillet: if you don't have an oven safe skillet (or Dutch oven), simply use a regular sauté pan and then transfer ingredients to a 13x9 baking dish. Cauliflower rice: either fresh or frozen will work! If you can't find riced cauliflower at the store, you can simply buy whole head and use a food processor or box grater to break it down into grain sized pieces.
- Preheat oven to 400°F.
- Measure olive oil into a large, oven safe skillet on the stove top and place on medium to medium high heat. (*tip: if you don't have an oven safe skillet, use a regular one and then transfer ingredients to a casserole dish before baking).
- Dice zucchini and squash and add to the skillet. Sauté for 8-10 minutes, stirring occasionally.
- Dice shallots and stir them into the zucchini & squash mixture. Continue to sauté for 2-3 more minutes.
- Add cauliflower rice, black beans, sweet corn, salt, pepper, garlic powder and half of your shredded cheddar. Gently stir all ingredients together until well combined. (*tip: if necessary, you can add cauliflower rice in shifts to help prevent overflow. As you stir it in, it'll cook down, giving you more space to work with).
- Pat squash mixture evenly into the skillet and sprinkle remaining cheese on top.
- Transfer to the oven and bake for 10 minutes.
- While your casserole bakes, chop up your parsley.
- Remove skillet casserole from the oven and allow it to cool. Sprinkle with fresh, chopped parsley.
- Plate and enjoy!
Did you make this recipe?!
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Leslie Watkins says
Looks amazing! Can’t wait to give this a try and add to my WW recipes!
Thanks, Leslie! Hope you enjoy it as much as we do!!
Jennifer Howard says
This looks AMAZING!!! I'm going to have zuc & summer squash any day now!!
Whoohooo!!! It is the BEST way to use up a whole bunch of squash and zucchini!
Connie Davis says
I haven't made this yet, but I'm hoping to try it soon. Can you used canned black beans?
Hi, Connie! Yes you can. Just drain and rinse them before adding. 🙂