Eggplant Casserole

1 (1 1/2 pound) eggplant
6 tablespoons butter
2 onions, sliced
3 sliced tomatoes (fresh) or 1 1/2 cups canned tomatoes
1 cup grated cheese
1 teaspoon salt
Pepper, to taste
1 cup finely crushed bread crumbs
Mushrooms (optional)

Slice the eggplant about 1/2 inch thick. Skin and dice. Makes about 5 cups.

Saut