Step 1

Slice zucchini into 1/2-inch rounds and place them in a colander. Sprinkle with salt and toss to coat. Let sit for 15 minutes to draw out moisture.

Step 2

Rinse zucchini slices thoroughly under cold water, then pat dry with paper towels.

Step 3

Heat olive oil in a large skillet over medium-high heat. Add diced onions and cook for 2 minutes until softened. Add the minced garlic and sauté for about 30 seconds until fragrant.

Step 4

Add the ground beef to the skillet and crumble it using a spoon. Continue cooking for about 5 minutes, until it’s browned and fully cooked through.

Step 5

Stir in the drained diced tomatoes, Italian seasoning, salt, and pepper. Remove from heat.

Step 6

Preheat oven to 350°F. Layer half of the beef mixture into an 8×8-inch baking dish, top with half the zucchini slices, and sprinkle with half the mozzarella cheese. Repeat layers.

Step 7

Place in the oven and bake for 20-25 minutes, or until cheese is melted and starting to brown.

Step 8

Let casserole sit for 10 minutes before slicing to help it set.