1 box cornbread mix (or your own recipe)
1 c. chopped onions
1/4 c. melted butter
3 c. chopped zucchini
1 c. milk
3 eggs
3/4 c. Parmesan cheese
Enough grated Cheddar cheese for top

Melt butter in an iron skillet or oven-proof pan. Mix all other ingredients and pour into pan, whipping in the butter slightly. Sprinkle cheese on top. Bake until golden brown, about 45 minutes in a 350 degree oven.