Preheat your oven to 400°F (200°C).

In a large bowl, toss the shredded zucchini with salt and allow it to sit for 10 minutes.

Thoroughly drain the zucchini in a fine mesh strainer.

Combine the drained zucchini with eggs, grated Parmesan cheese, and half of the shredded mozzarella.

Grease a 9x13-inch baking dish and press the zucchini mixture into the bottom to form the crust.

Bake in the preheated oven for 20 minutes until lightly browned.

Cook the ground beef and chopped onion in a skillet over medium-high heat until browned.

Stir in pizza sauce, green bell pepper, sliced mushrooms, dried oregano, garlic powder, and black pepper. Let simmer for 5 minutes.

Spread the savory mixture over the baked crust.

Sprinkle remaining mozzarella and cheddar cheese over the filling.

Return to the oven and bake for another 20 minutes until cheese is melted and bubbly.

Let cool for a few minutes, slice into squares and serve warm.