Yellow Squash and Zucchini Casserole Recipe photo by Taste of Home

Yellow Squash and Zucchini Casserole

Total Time
Prep: 25 min. Bake: 10 min.
This simple yellow squash and zucchini casserole is the perfect side dish to serve all summer long. Like a gratin, the squash bakes with cream, cheese and bread crumbs for a savory richness that pairs well with everything.

Updated: Jun. 11, 2024

Who said you should only eat casseroles in colder months? We have just the recipe when you crave a flavorful casserole in the summer and your garden overflows with produce: yellow squash and zucchini casserole.

Like a gratin, this dish is lighter than many other casserole recipes, and it makes a perfect side dish for summer barbecues and gatherings. This casserole is one of those summer squash and zucchini recipes to enjoy time and again.

Yellow squash and zucchini contain around 95% water, which risks turning a casserole soggy. To combat that moisture, this recipe precooks the summer squash and zucchini, along with shallots and garlic, until everything is tender and flavorful. A splash of cream and a sprinkle of cheese and bread crumbs complete the casserole, which bakes in the oven until soft and bubbly. Extra cheese and bread crumbs on top add even more flavor and texture.

Ingredients for Yellow Squash and Zucchini Casserole

  • Butter: Cooking the yellow squash and zucchini in butter helps release moisture in the vegetables while taking on more flavor.
  • Zucchini: Zucchini is a green summer squash known for its mild, almost sweet flavor. Zucchini recipes range from savory to sweet.
  • Yellow summer squash: There are many types of summer squash, but we like this variety because its bright color adds visual interest to all kinds of dishes.
  • Shallots and garlic: Milder than onions, shallots add a savory flavor that won’t overwhelm the mild squash in this recipe. A bit of garlic makes this casserole taste extra rich.
  • Salt and pepper: Season your casserole generously since squash and zucchini contain lots of water.
  • Heavy whipping cream: This recipe calls for a splash of heavy whipping cream, which binds everything together and makes the casserole taste indulgent. Heavy cream and whipping cream are interchangeable in this recipe.
  • Panko bread crumbs: Panko bread crumbs are an extra-crunchy, super-light Japanese version of bread crumbs. They add a lot of texture and crunch to this vegetable casserole.
  • Parmesan cheese: No casserole is complete without a bit of cheese. Here, we use Parmesan for its nutty, umami richness.

Directions

Step 1: Cook the vegetables

Preheat your oven to 450°F. Heat a large skillet over medium heat, then add your butter. Add the zucchini, yellow squash and shallots to the pan when the butter fully melts. Sprinkle with salt and pepper, then cook, stirring, until the vegetables start to brown and are crisp-tender, four to six minutes. Add the garlic, and cook for another minute.

Editor’s Tip: Use the largest skillet possible for this process, which will help prevent crowding the pan. A less crowded pan allows more water to evaporate, resulting in a more delicious result.

Step 2: Add the cream and cheese

Add the cream to the mixture in skillet, and cook until thickened, three to five minutes. Remove the skillet from heat, and stir in 1/2 cup bread crumbs and 1/4 cup cheese.

Step 3: Bake the casserole

Spoon the mixture into an 11×7-inch or a 2-quart baking dish. Sprinkle the mixture with the remaining bread crumbs and cheese, then bake until golden brown, 8 to 10 minutes.

Editor’s Tip: Allow the casserole to cool slightly before serving. You want it to set up just a bit before scooping out the veggies.

Recipe Variations

  • Try another type of summer squash: With so many types of squash available in the summer months, try this recipe with pattypan squash, round zucchini or the elongated tromboncino squash.
  • Cut the squash differently: For a slight variation on this recipe, try dicing your squash into cubes rather than slicing them into rounds. The change in cutting style will change the texture of the dish.
  • Add fresh herbs: Ribbons of basil, chopped thyme, a bit of rosemary, or other types of herbs make this dish a true summer showstopper.
  • Add bacon: Fold slices of cooked bacon into the casserole before you transfer it to the oven for a richer, meatier version of this dish.

How to Store Yellow Squash and Zucchini Casserole

Yellow squash and zucchini casserole will last up to four days in the refrigerator. Store it in an airtight container until you’re ready to eat it. Reheat the casserole in the microwave or the oven.

How to Freeze Yellow Squash and Zucchini Casserole

Yellow squash and zucchini casserole freezes well. Bake it thoroughly, and allow the dish to cool completely for the best result. Wrap the casserole tightly in storage wrap or aluminum foil, and transfer it to the freezer, where it will last up to three months. To reheat, let the dish fully thaw in the refrigerator before baking it uncovered until heated.

Yellow Squash and Zucchini Casserole Tips

How can you prevent watery yellow squash and zucchini casserole?

Yellow squash and zucchini are very watery vegetables, so they’ll release lots of water as they cook. We add bread crumbs and cheese to help absorb some of that liquid. We also recommend measuring the cream you add to the recipe to avoid adding too much liquid. Cooking the casserole uncovered allows some moisture to evaporate during the cooking process.

What do you serve with yellow squash and zucchini casserole?

This yellow squash and zucchini casserole is like a gratin, so it pairs well with anything you might typically serve with au gratin or scalloped potatoes. Try it with your favorite grilled steak recipes or grilled salmon fillets. It makes a lovely vegetarian main dish, especially paired with summer salads.

Watch how to Make Yellow Squash and Zucchini Casserole

Yellow Squash and Zucchini Casserole

Prep Time 25 min
Cook Time 10 min
Yield 6 servings

Ingredients

  • 2 tablespoons butter
  • 2 medium zucchini, cut into 1/4-inch slices
  • 2 medium yellow summer squash, cut into 1/4-inch slices
  • 2 shallots, minced
  • 1/2 teaspoon sea salt
  • 1/4 teaspoon coarsely ground pepper
  • 4 garlic cloves, minced
  • 1/2 cup heavy whipping cream
  • 1 cup panko bread crumbs, divided
  • 1/2 cup grated Parmesan cheese, divided

Directions

  1. Preheat oven to 450°. In a large skillet, melt butter over medium heat; add zucchini, yellow squash and shallots. Sprinkle with salt and pepper. Cook, stirring occasionally, until vegetables are crisp-tender, 4-6 minutes. Add garlic; cook 1 minute more.
  2. Add the cream; cook until thickened, 3-5 minutes. Remove from heat; stir in 1/2 cup bread crumbs and 1/4 cup cheese. Spoon mixture into a greased 11x7-in. or 2-qt. baking dish. Sprinkle with remaining bread crumbs and cheese. Bake until golden brown, 8-10 minutes.

Nutrition Facts

1 cup: 203 calories, 14g fat (8g saturated fat), 39mg cholesterol, 357mg sodium, 15g carbohydrate (4g sugars, 2g fiber), 6g protein.

This yellow squash and zucchini casserole is the perfect way to use up an abundance of summer squash. It's easy to prepare, takes just 10 minutes in the oven and serves up bubbly and delicious. —Jonathan Lawler, Greenfield, Indiana
Recipe Creator