Cheesy Baked Zucchini Casserole

Prep Time: 20 minutes
Cook Time: 40 minutes
Total Time: 1 hour
Course: Main Course, Side Dish
Cuisine: Italian-American
Servings: 6-8 servings
Calories: ~410 kcal per serving (based on 8 servings)

Table of Contents

Ingredients

For the Zucchini:

4 large zucchini (about 2.5 lbs / 1.1 kg)
1 tablespoon olive oil
Salt and black pepper, to taste

For the Meat Sauce:

1 lb (450g) ground Italian sausage (mild or spicy) or ground turkey
1 small yellow onion, diced
3 cloves garlic, minced
1 (24-ounce / 680g) jar of your favorite marinara sauce
1 teaspoon Italian seasoning
½ teaspoon red pepper flakes (optional, for heat)

For the Cheese Mixture:

1 (15-ounce / 425g) container of whole-milk ricotta cheese
1 large egg
½ cup grated Parmesan cheese, divided
¼ cup fresh basil or parsley, chopped (plus more for garnish)
¼ teaspoon salt
¼ teaspoon black pepper

For the Topping:

2 cups (8 oz / 225g) shredded low-moisture mozzarella cheese

Equipment

Large skillet
9×13 inch (23×33 cm) baking dish
Colander
Clean kitchen towel or paper towels
Mixing bowls
Whisk
Wooden spoon or spatula

Instructions

Step 1: Prepare the Zucchini (Intensity: Low)

Preheat your oven to 400°F (200°C). Lightly grease a 9×13 inch baking dish with olive oil or non-stick spray.

Slice the zucchini into ¼-inch thick rounds. Place the slices in a colander, sprinkle them generously with salt, and let them sit for 10-15 minutes. This process, called “sweating,” draws out excess moisture, preventing a watery casserole.

After 15 minutes, gently press the zucchini slices with paper towels or a clean kitchen towel to remove as much moisture as possible. Drizzle with a little olive oil and toss to coat.

Step 2: Make the Meat Sauce (Intensity: Medium)

While the zucchini is sweating, heat a large skillet over medium-high heat. Add the ground sausage and cook, breaking it up with a wooden spoon, until browned and cooked through (about 5-7 minutes). If using ground turkey, add a tablespoon of olive oil first.

Add the diced onion and cook for another 3-4 minutes until softened. Stir in the minced garlic and cook for 1 minute until fragrant.

Pour in the marinara sauce, Italian seasoning, and red pepper flakes (if using). Bring the sauce to a simmer, then reduce the heat to low and let it cook for 10 minutes to allow the flavors to meld. Season with salt and pepper to taste.

Step 3: Prepare the Cheese Mixture (Intensity: Low)

In a medium mixing bowl, combine the ricotta cheese, egg, ¼ cup of the grated Parmesan, chopped basil/parsley, salt, and pepper. Whisk until smooth and well combined. Set aside.

Step 4: Assemble the Casserole (Intensity: Low)

Spread a thin layer (about ½ cup) of the meat sauce on the bottom of the prepared baking dish. This prevents sticking.

Arrange half of the zucchini slices in a single, slightly overlapping layer over the sauce. Dollop half of the ricotta mixture evenly over the zucchini, then gently spread it out. Top with half of the remaining meat sauce, followed by 1 cup of the shredded mozzarella.

Repeat the layers: the remaining zucchini, the rest of the ricotta mixture, and the rest of the meat sauce.

Step 5: Bake the Casserole (Intensity: Low)

Sprinkle the remaining 1 cup of mozzarella and the remaining ¼ cup of Parmesan cheese over the top of the casserole.

Cover the baking dish with foil and bake for 20 minutes. Then, remove the foil and continue to bake for another 20-25 minutes, or until the cheese is melted, bubbly, and golden brown on top.

Step 6: Rest and Serve (Intensity: Low)

Once out of the oven, let the casserole rest for at least 10-15 minutes. This is a crucial step! Resting allows the layers to set, making it easier to slice and serve.

Garnish with fresh chopped basil or parsley and serve hot. Enjoy!

Recipe Notes & Tips

The Secret to Non-Watery Casserole: The most important step is salting and draining the zucchini. Do not skip this! It makes a world of difference in the final texture.
Vegetarian Version: Omit the meat and add a layer of sautéed mushrooms or lentils to the sauce for a hearty vegetarian meal. Use a vegetarian marinara sauce.
Make-Ahead: You can assemble the casserole up to 24 hours in advance. Cover and refrigerate. When ready to bake, add 10-15 minutes to the covered baking time.
Storage: Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat in the microwave or oven until warmed through.
Freezing: This casserole freezes well. Assemble the casserole in a freezer-safe dish, cover tightly, and freeze for up to 3 months. Thaw overnight in the refrigerator before baking as directed.

Nutrition Information

Serving Size: 1/8 of the casserole

Calories: 410
Total Fat: 26g
Saturated Fat: 12g
Cholesterol: 95mg
Sodium: 980mg
Total Carbohydrates: 12g
Dietary Fiber: 2g
Total Sugars: 7g
Protein: 27g

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