Pizza Casserole - cooking recipe

Ingredients

1 (4 oz.) pkg. sliced pepperoni
1 medium onion, chopped fine
1 (6 oz.) pkg. thin spaghetti, cooked and drained
1 c. grated Swiss cheese
1 lb. Mozzarella cheese, sliced thin
3 (8 oz.) cans tomato sauce
1 (4 oz.) can mushroom pieces, drained
1/2 tsp. oregano or 1 tsp. Italian seasoning
1/2 tsp. basil

Preparation

Saute onion in 1 1/3 tablespoons butter. Heat oven to 350\u00b0. Pour remaining 1/4 cup butter into 11 x 7 x 2 baking dish. Toss cooked spaghetti in butter. Cover spaghetti with 1 1/2 cans tomato sauce. Add in order listed:
1/2 pepperoni, 1/2 Mozzarella and all the onions and mushrooms. Sprinkle with Italian seasoning. Pour on top of this 1 1/2 cans tomato sauce. Top with remainder of Swiss cheese, pepperoni and lastly Mozzarella cheese. Bake 20 to 25 minutes in 350\u00b0 oven until bubbly. Serves 6.