Zucchini Pizza Casserole

Ok, ok, now my friend Ellen dropped off a bag of huge zucchini so tonight I made this to use my zucchini and tomatoes together...I just cut up and added in 3 tomatoes to this recipe.
* 4 cups shredded unpeeled zucchini
* 1/2 teaspoon salt
* 2 eggs
* 1/2 cup grated Parmesan cheese
* 2 cups (8 ounces) shredded part-skim mozzarella cheese, divided
* 1 cup (4 ounces) shredded cheddar cheese, divided
* 1 pound ground beef
* 1/2 cup chopped onion
* 1 can (15 ounces) Italian tomato sauce
* 1 medium green pepper, chopped

Directions

* Place zucchini in strainer; sprinkle with salt. Let stand for 10 minutes. Squeeze out moisture.
* Combine zucchini with the eggs, Parmesan and half of the mozzarella and cheddar cheeses. Press into greased 13-in. x 9-in. baking dish.
* Bake, uncovered, at 400° for 20 minutes. Meanwhile, cook beef and onion over medium heat until meat is no longer pink; drain. Add tomato sauce; spoon over zucchini mixture.
* Sprinkle with remaining cheeses; add green pepper. Bake 20 minutes longer or until heated through. Yield: 6-8 servings.