Sink your fork into the irresistible, supremely comforting Cheesy Ground Beef and Zucchini Casserole—a wonderfully hearty dish that turns simple, everyday ingredients into a family favorite. This recipe melds the savory depth of ground beef with the garden freshness of zucchini, then ties it all together with gooey layers of cheddar and mozzarella cheese. Each bite is creamy, cheesy, and packed with flavor, making this casserole perfect for everything from cozy weeknight dinners to casual gatherings. It’s one of those special recipes you’ll want to make on repeat!

Cheesy Ground Beef and Zucchini Casserole Recipe - Recipe Image

Ingredients You’ll Need

It’s amazing how a handful of humble ingredients come together to make Cheesy Ground Beef and Zucchini Casserole a standout dish. Every component brings its own magic—whether that’s richness, brightness, texture, or a little zing of flavor.

Ground beef: The foundation of our casserole, providing hearty flavor and a robust, meaty texture.
Zucchini: Sliced for tender bites, zucchini adds moisture and a hint of sweetness that balances the rich beef and cheese.
Onion: Diced onion brings subtle sweetness and depth to the base of the casserole.
Garlic: Minced garlic infuses the dish with a warm, aromatic kick—don’t skip it!
Diced tomatoes: A can of diced tomatoes adds tang, juiciness, and a pop of color to the mix.
Cheddar cheese: Shredded cheddar melts to deliver a sharp, creamy layer that marries all the flavors together.
Mozzarella cheese: This cheese is all about stretch—expect bubbly, golden perfection on top.
Sour cream: Sour cream gives a rich, velvety consistency that keeps every bite luscious and satisfying.
Italian seasoning: A quick way to add herbaceous notes—think basil, oregano, and maybe a whisper of thyme.
Salt and pepper: Classic seasoning that brings out the best in all the other flavors.
Red pepper flakes (optional): A pinch offers gentle heat for those who like a little spicy kick.
Olive oil: Just a drizzle to start the beef and vegetables off right, boosting richness.

How to Make Cheesy Ground Beef and Zucchini Casserole

Step 1: Preheat the Oven and Prepare the Baking Dish

Start your journey to comfort food bliss by setting your oven to 375°F (190°C). A well-greased 9×13-inch baking dish ensures nothing sticks and helps those cheesy edges crisp up beautifully. Preparing the dish is a small step that pays off when your casserole slides out effortlessly later.

Step 2: Cook the Beef, Onions, and Garlic

In a large skillet, warm up the olive oil over medium heat. Toss in your diced onion and minced garlic, letting them sauté until the kitchen smells wonderfully fragrant and the onions look translucent. Next, crumble in your ground beef and cook, stirring occasionally, until it’s browned and sizzling. If there’s excess fat, give it a quick drain—this keeps the casserole from getting greasy and lets the other flavors shine through.

Step 3: Add the Zucchini and Tomatoes

Stir in the sliced zucchini, drained diced tomatoes, Italian seasoning, salt, black pepper, and the optional red pepper flakes. This step brings the Cheesy Ground Beef and Zucchini Casserole to life: the zucchini softens, the tomatoes break down a bit, and a medley of seasoning infuses everything. Let this mixture simmer for about 5 minutes, just until the zucchini begins to look slightly tender but still fresh and green.

Step 4: Stir in the Sour Cream

Take the skillet off the heat and gently fold in the sour cream. This moment transforms the filling from a simple stew to something creamy and indulgent—the sour cream melts in, making every scoop delightfully smooth. Make sure it’s evenly distributed for maximum lusciousness throughout your casserole.

Step 5: Assemble the Casserole

Carefully transfer your beef and zucchini mixture into the greased baking dish, spreading it out so every serving gets a little of everything. Sprinkle the shredded cheddar and mozzarella cheese evenly across the top. As this melts, it’ll bubble into an irresistible golden crust—arguably the best part of Cheesy Ground Beef and Zucchini Casserole!

Step 6: Bake Until Golden and Bubbly

Slide your creation into the preheated oven and bake for about 20 minutes, or until the cheese is fully melted, bubbling, and beginning to brown in spots. Let the casserole rest for a few minutes before serving so everything sets up nicely and you get clean, perfect slices.

How to Serve Cheesy Ground Beef and Zucchini Casserole

Garnishes

A sprinkle of chopped fresh parsley or basil right before serving adds a fresh, herby contrast to all the cheesy richness. For a pop of bright flavor, a quick zesting of lemon is surprisingly delightful! You could also add thinly sliced green onions or a dusting of extra red pepper flakes for a little heat.

Side Dishes

Pair your Cheesy Ground Beef and Zucchini Casserole with a simple green salad tossed in a zesty vinaigrette, or serve alongside some freshly baked garlic bread for a truly satisfying meal. Roasted vegetables or even a scoop of mashed potatoes work beautifully as well, especially if you’re craving extra comfort.

Creative Ways to Present

For a weeknight wow-factor, serve generous scoops in shallow bowls and top each with a tumble of crisp microgreens. If you’re entertaining, try portioning the casserole into individual ramekins before baking for a fun, personalized touch. You can even turn leftovers into the filling for a rustic sandwich or stuffed peppers the next day!

Make Ahead and Storage

Storing Leftovers

Leftovers of this Cheesy Ground Beef and Zucchini Casserole store beautifully. Just let the casserole cool completely, cover the dish with plastic wrap or foil, or transfer portions into airtight containers. You can refrigerate them for up to four days—making lunch or dinner a breeze!

Freezing

This casserole is freezer-friendly too! For best results, wrap individual pieces or the whole tray tightly in plastic wrap and then foil. Label and freeze for up to 2-3 months. When you’re ready to enjoy, defrost it overnight in the fridge before reheating.

Reheating

To reheat, pop a casserole slice in the microwave for a fast lunch, or bake covered in a 350°F oven until warmed through (about 20 minutes). Adding a sprinkle of extra cheese before reheating in the oven brings back that delicious melted topping.

FAQs

Can I use ground turkey or chicken instead of beef?

Absolutely! Ground turkey or chicken will work just as well and make the casserole a bit lighter, though you may want to add an extra pinch of seasoning to boost the flavor.

Do I need to peel the zucchini for this recipe?

No need to peel—zucchini skin is thin, adds a pop of color, and holds up well during baking. Just give them a quick rinse and slice away.

Is this Cheesy Ground Beef and Zucchini Casserole gluten-free?

Yes, the ingredients listed contain no gluten, making this casserole naturally gluten-free. Just check your labels (especially on sour cream and cheese) to be sure!

Can I prepare the casserole in advance?

Definitely! You can assemble the casserole up to a day ahead, cover, and keep it in the fridge. Just bake it when you’re ready to serve, adding a couple of extra minutes to the baking time if it’s cold from the fridge.

How can I make this casserole even more flavorful?

Try adding a sprinkle of extra Italian herbs, a dash of smoked paprika, or even a few sun-dried tomatoes for extra punch. A handful of fresh basil stirred into the filling before baking is another delicious twist.

Final Thoughts

If you’re ready to bring big smiles to the dinner table, you can’t go wrong with Cheesy Ground Beef and Zucchini Casserole. This dish hits all the high notes of comfort food and is sure to become a staple in your recipe collection. I hope you’ll give it a try—your future self (and your hungry eaters) will thank you!