1 8-oz rotini pasta
1 lb. lean ground beef
1 small onion, diced
1 (28-oz) jar spaghetti sauce
1 4-oz sliced pepperoni sausage
2 c. shredded mozzarella cheese

Preheat oven to 350°F. Bring a large pot of lightly salted water to a boil. Add pasta and cook for 8 to 10 minutes or until al dente; drain. In medium skillet over medium high heat, cook beef with onion until beef is brown. Drain. Combine beef mixture with spaghetti sauce, pepperoni and cooked pasta and pour into a 9 x 13 inch baking dish. Top with mozzarella.

Bake in preheated oven for 30 minutes, until cheese is melted and golden.