1) Cook butter onions and garlic in a large skillet on low heat till onion is limp.
2) Grease a 2 quart casserole pan put onion mixture, then layer with chopped zucchini
3) Beat eggs and add salt and pepper. pour over zucchini mixture
4) Sprinkle with 1 cup grated parmesan cheese.
5) Cover and bake 300 degrees for 1 hour or more.
6) After removing from oven add cheddar cheese and place cover back on dish until cheese is melted.
7) Can be cooked on skillet on top of stove, but oven is better.