1 lb. ground beef
2 cans tomato sauce
1 tsp. oregano
2 c. Bisquick
1 egg
2/3 c. milk
8 slices American cheese
1 can sliced mushrooms
1/2 c. grated Parmesan

Heat oven to 400 degrees. Cook and stir ground beef until brown; drain. Mix in 1 can tomato sauce and oregano. Simmer, uncovered for 10 minutes. Stir baking mix, egg, and milk to a soft dough. Spread half of dough in greased pan. Pour remaining can of tomato sauce over dough spreading evenly. Layer 4 slices of cheese, the meat mixture, mushrooms, then remaining cheese slices and Parmesan cheese, then spread remaining dough over top. Bake 25 minutes.