Toss zucchini with 1 teaspoon salt and let stand 20 minutes; drain. Place half of the zucchini in a buttered 2-quart casserole. Heat oil in skillet; sauté onion and garlic until tender; add ground beef and cook until no longer pink. Drain off excess fat; add oregano, pepper, and 1/2 teaspoon salt or more to taste. Stir in rice and tomato sauce. Spread over zucchini in casserole. Combine ricotta cheese, 1/2 cup Cheddar cheese, and egg; spoon over meat mixture.
Top with remaining zucchini and sprinkle with remining Cheddar cheese. Bake in
preheated 350° oven 20 to 25 minutes, or until bubbly.
Calories per serving: 445
Fat per serving: 18.3g