1 1/2 lbs. hamburg, browned
1 med. onion
2/3 box rigatoni noodles, cooked
2 cans (1 qt.) pizza sauce
2 (8 oz.) pkgs. Mozzarella cheese
1 pkg. pepperoni
1 can mushrooms, drained

Layer in order given 3 times in crock pot. Cook on low 5 hours. I use regular noodles.