Cheesy Zucchini Casserole
This tasty zucchini casserole has it all—creamy cheesy sauce, lots of tender zucchini, and a buttery crunchy topping.
This cheesy zucchini casserole recipe is the perfect side dish for a family meal or special occasion dinner. From the creamy, cheesy filling to the cheddar and buttery breadcrumb topping, it is bound to please. With a combination of zucchini, creamy cheese sauce, and a buttery breadcrumb topping, my cheesy zucchini casserole is both hearty and versatile. It’s an excellent side dish to pair with your favorite entrees. It pairs nicely with hamburger steaks, pork chops, roasted chicken, and baked ham.
The star of the dish is zucchini, a mild, adaptable vegetable that takes on the flavors of its surrounding ingredients. The tender-cooked zucchini and onions are combined with an easy, seasoned cheese sauce. The casserole is topped with more cheese and buttery panko crumbs, making it savory, rich, and crunchy.
I used mild cheddar cheese for its excellent melting properties, but feel free to use another cheese. Gruyère would work well, or choose sharp cheddar or a Monterey Jack blend.
Add the casserole to your weekly or monthly menu rotation, and if zucchini is in season, all the better. If you don’t have an abundance of zucchini in your garden, you’ll find it’s readily available and reasonably priced in the supermarket and farmers’ markets.
Why You’ll Love It
Comforting and creamy. Layers of tender zucchini and smooth cheese sauce make a deliciously rich side.
Simple ingredients. Everything you need is likely already in your kitchen.
Perfect texture. Creamy center, melty cheese, and crisp buttery topping.
Versatile pairing. Great with chicken, pork, steak, or ham.
Ingredient Notes
- Zucchini: Choose medium, firm zucchini for the best flavor and texture.
- Cheese: Mild cheddar melts beautifully, but Gruyère, sharp cheddar, or Monterey Jack also work.
- Breadcrumbs: Panko gives a light crunch; mix with melted butter for an evenly golden crust.
- Mustard powder: Adds a subtle tang that enhances the cheese flavor.
- Onion: A bit of diced onion adds sweetness and depth to the sauce.
Steps to Make Cheesy Zucchini Casserole
- Preheat the oven and butter a casserole dish. Sauté the onion in butter until fragrant, then add the sliced zucchini and cook until just tender. Transfer the mixture to the baking dish.
- Make a simple cheese sauce by melting butter, whisking in flour, and gradually adding milk until thickened. Stir in the seasoning and part of the cheese, then pour the sauce over the zucchini.
- Top with the remaining cheese and buttery panko crumbs, then bake until bubbling and golden brown around the edges. Serve warm for the ultimate comforting side.
Recipe Variations
- Protein: Make it a hearty main dish with the addition of browned ground beef or sausage, or some diced leftover ham or chicken.
- Spicy Twist: Add some minced jalapeño peppers or use pepperjack cheese for a pleasant bit of heat.
- Herbs: Mix in fresh chopped herbs, such as basil, thyme, or parsley.
- Italian: Add a drizzle of marinara sauce and use fresh mozzarella for the topping.
How to Store and Reheat
Refrigerate. Cover and refrigerate leftovers for up to 4 days.
Freeze? Not ideal — the texture softens — but can be frozen up to 2 months if needed.
To Reheat. Cover with foil and warm in a 350 °F oven for 15–20 minutes, stirring once for even heating. Heat to 165°F before serving.
Cheesy Zucchini Casserole
Ingredients
- 1/2 cup unsalted butter, (4 ounces), divided
- 3/4 cup diced onion
- 6 cups zucchini, sliced, about 2 pounds
- 2 tablespoons flour
- 1 cup whole milk
- 3/4 teaspoon fine sea salt, or to taste
- 1/4 teaspoon mustard powder
- 1/4 teaspoon freshly ground black pepper
- 1 1/2 cups mild cheddar cheese, shredded , divided
- 1 cup panko breadcrumbs
Instructions
- Heat the oven to 350°F and butter a 1 1/2-quart baking dish.
- Melt 4 tablespoons of butter in a large skillet over medium heat. Add the chopped onion and cook, stirring, for 2 minutes. Add the sliced zucchini, cover the pan, and reduce the heat to low. Cook for 8 minutes or until the zucchini is just tender. Remove the zucchini and onions to the baking dish with a slotted spoon.
- Wipe out the skillet, add 2 tablespoons of butter, and melt it over medium heat, then stir in the flour. Cook for 2 minutes, then gradually add the milk. Taste and add the salt, mustard powder, black pepper, and 1/2 cup of the cheese. Cook, stirring, until hot and thickened. Pour the mixture over the zucchini mixture in the baking dish.
- Melt the remaining 2 tablespoons of butter and toss with the panko crumbs.
- Sprinkle the remaining cheese over the casserole, followed by the buttered panko crumbs.
- Bake for 25 minutes or until the topping is browned and the casserole is bubbling around the edges.
Nutrition
Disclaimer:
Our nutritional information is based on a third-party application that analyzes the ingredients list to determine the values. The information is meant to be helpful, but should be considered an estimate. Values may differ depending on measurements, brands, serving variations, and database availability.
