1-1/2 lbs. hamburger
1 med. onion, chopped
2 cans spaghetti sauce
2/3 pkg. rigatoni pasta, uncooked
3 lbs. mozzarella cheese
olives, peppers, mushrooms - optional
Brown hamburger & onion together and drain. Mix in sauce. Make alternate layers in crock pot, starting with meat sauce, noodles, pepperoni, olives, peppers, & mushrooms (if using) & cheese. Ending with a cheese layer on top.
Cook on low for 5 hours.
***I would recommend leaving off the top layer of cheese & adding it about 30 min-1 hr before it's done. Otherwise the top layer of cheese starts to burn around the edges.