This cheesy zucchini casserole is rich, garlicky, and baked to perfection. A zucchini casserole recipe that's creamy, crisp, and flavorful!

My friends who have kids and I love making the most of summer when zucchini is everywhere. This cheesy zucchini casserole has become a favorite in our homes—one that the kids never turn down. It's so good that my little ones always ask for seconds. Be it a quick side dish or a light main course, it’s a go-to for busy nights.
The way the cheese and herbs transform plain zucchini into something we all crave is amazing. A golden, bubbly cheese crust hides tender vegetable underneath, making this the rare vegetable dish that actually excites my kids. They're usually too distracted by the melty cheese to notice they're eating a pan full of vegetables.
What makes this recipe brilliant is its simplicity. While the kids are busy playing or watching, I can quickly prep the zucchini and pop it in the oven. The hands-off baking time allows me to make other food to complete our meal. Plus, the recipe allows you to add different cheeses or herbs based on what you need to use up in your fridge.
This has become a staple not just during summer when zucchini is cheap and plenty, but any time I want a guaranteed cleaned-up veggie plate. The leftovers are great too—I often pack them in lunch boxes or reheat for an easy side with the next day's dinner.
If you're trying to add more vegetables to your family's diet or just need an easy side dish that everyone will eat, this casserole is a perfect recipe to add to your list. The combination of tender zucchini, melty cheese, and savory herbs creates something that tastes indulgent while sneaking in those vegetables. My favorite sound? The scraping of plates as everyone tries to get the last cheesy bite.
Ingredients

- Zucchini - thinly sliced, serves as the main ingredient.
- Mozzarella - shredded, adds a creamy and stretchy texture.
- Sharp cheddar - shredded, contributes a bold and tangy flavor that complements the other cheeses.
- Parmesan - grated, adds a salty and nutty flavor.
- Sour cream - adds creaminess and a slight tang, helping to bind the ingredients together.
- Shallots - minced, provide a mild onion flavor.
- Garlic - minced, contributes aromatic flavor.
- Fresh thyme leaves - add an herbal note.
- Unsalted butter - used for sautéing.
- Panko breadcrumbs - provide a crispy topping, adding texture and crunch to the finished dish.
- Olive oil - used for cooking.
See the recipe card for exact quantities.
Step-by-step Instructions

If you're in the mood for a comforting and cheesy dish, this cheesy zucchini casserole is a fantastic choice! Packed with layers of zucchini, creamy cheeses, and flavorful seasonings, it's easy to make and perfect for a family meal or a potluck. Just follow the simple steps below to create this delicious casserole!
Preheat the Oven
Begin by preheating your oven to 375°F (190°C). This ensures that the casserole will cook evenly and thoroughly once assembled.
Sauté Shallots and Garlic

In a medium-sized pan, heat a drizzle of olive oil over medium heat. Add the minced shallots and garlic to the pan. Sauté them for about 3-5 minutes, or until they become soft and fragrant. Be careful not to let them brown, as this can affect the flavor of the dish.
Prepare the Cheese Mixture

In a mixing bowl, combine the shredded mozzarella and sharp cheddar cheese. Set aside 1 cup of this cheese mixture for the topping later. This will add a cheesy layer on top of the casserole for extra flavor and texture.
Layer the Casserole



In a 9x13-inch baking dish, start layering the ingredients. Begin with a layer of ¼ of the sliced zucchini, followed by ¼ of the sautéed shallot and garlic mixture. Next, add ¼ of the cheese mixture and then ¼ of the sour cream. Season this layer with salt, pepper, and fresh thyme leaves. Repeat these layers three more times, finishing with the last of the zucchini, shallots, cheese, and sour cream.
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Prepare the Topping


In a small bowl, mix the panko breadcrumbs with the melted unsalted butter, the reserved cheese, and the grated Parmesan cheese. This mixture will create a crispy topping for the casserole. Once combined, sprinkle this topping evenly over the assembled casserole.
Bake the Casserole

Place the baking dish in the preheated oven and bake for 40-45 minutes. The casserole is done when it is golden brown on top and bubbly around the edges. Keep an eye on it to ensure it doesn’t overcook.
Optional Broiling Step

If you prefer a crispier top, you can switch the oven to broil for an additional 2-3 minutes after baking. This will help achieve a nice golden crust. Be sure to watch it closely during this time to prevent burning.
Rest Before Serving

Once baked, remove the casserole from the oven and let it rest for about 10 minutes. This resting period allows the layers to set, making it easier to serve. After resting, cut into portions and serve hot. Enjoy your cheesy zucchini casserole!
Storage

To store cheesy zucchini casserole, allow it to cool to room temperature after baking. Once cooled, transfer the casserole to an airtight container or cover it tightly with plastic wrap. Refrigerate the casserole for up to 3-4 days. When you're ready to enjoy the leftovers, you can reheat individual portions in the microwave or place the entire casserole back in the oven at 350°F (175°C) until heated through. Enjoy your leftovers!
Top Tips
Use a Mandoline for even slices: To achieve uniform thickness in your zucchini slices, consider using a Mandoline slicer. This will help the zucchini cook evenly and ensure that each layer has the same texture.
Drain excess moisture: Zucchini can release a lot of moisture during cooking. To prevent the casserole from becoming watery, you can sprinkle the sliced zucchini with salt and let it sit for about 15-20 minutes. Afterward, pat the slices dry with a paper towel to absorb excess moisture before layering.
Mix up the cheeses: While mozzarella and cheddar are great choices, feel free to experiment with other cheeses for added flavor. Consider adding Gruyère, Monterey Jack, or even a bit of feta for a different taste profile in your casserole. Mixing cheeses can enhance the richness and complexity of the dish.
What to Serve Cheesy Zucchini Casserole

Cheesy zucchini casserole pairs well with a mix of proteins, fresh salads, and other comforting bakes. For those looking for a light yet flavorful option, fire-grilled Nordic salmon or oven-baked pomegranate salmon bring depth to the meal without overpowering the zucchini. If you prefer chicken, air fryer chicken thighs add a crisp texture that balances the creamy casserole.
For freshness, a bright salad works well alongside the dish. Little gem salad provides crunch, while kale salad or quinoa salad add more substance with a mix of textures and flavors. If you want another baked dish on the table, cabbage casserole, salmon casserole with cauliflower, baked rutabaga casserole, or chicken hashbrown casserole can round out the table with different layers of flavor and texture.
Recipe
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Cheesy Zucchini Casserole
Equipment
- Mandoline slicer optional
Ingredients
- 3 ⅓ lbs zucchini thinly sliced
- 3 cups mozzarella shredded
- 3 cups sharp cheddar shredded
- 1 cup Parmesan grated
- 1 ¼ cups sour cream
- 2 shallots minced
- 3 garlic cloves minced
- 2 tablespoon fresh thyme leaves
- ¼ cup unsalted butter
- ½ cup panko breadcrumbs
- 2 tablespoon olive oil
- Salt and freshly ground black pepper to taste
Instructions
- Preheat oven to 375°F (190°C).
- In a pan, sauté shallots and garlic in olive oil until soft.
- In a bowl, combine mozzarella and cheddar. Set aside 1 cup for topping.
- In a 9x13-inch baking dish, layer ¼ of the zucchini, followed by ¼ of the shallot mixture, ¼ of the cheese mix, and ¼ of the sour cream. Season with salt, pepper, and thyme. Repeat layers three more times.
- Mix panko with melted butter, reserved cheese, and Parmesan. Sprinkle over the casserole.
- Bake for 40-45 minutes until golden and bubbly.
- If desired, broil for 2-3 minutes for a crispier top.
- Let rest for 10 minutes before serving hot.







