2 cups uncooked spiral pasta
2 pounds ground beef
2 small onions, chopped
1 garlic clove, minced
1 jar (26 ounces) spaghetti sauce
1 jar (4-1/2 ounces) sliced mushrooms, drained
1/2 cup sour cream
1/2 pound process cheese (Velveeta), cubed
2 cups (8 ounces) shredded part-skim mozzarella cheese
Cook pasta according to package directions. Meanwhile, in a large saucepan, cook the beef, onions and garlic over medium heat until meat is no longer pink; drain.
Stir in spaghetti sauce and mushrooms; bring to a boil. Reduce heat; cover and simmer for 20 minutes.
Place 1/2 cup of meat sauce in a greased shallow 2-1/2-qt. baking dish.
Drain pasta; place half over sauce.
Top with half of the remaining meat sauce; spread with sour cream.
Top with process cheese and remaining pasta and meat sauce.
Sprinkle with mozzarella cheese.
Cover and bake at 350° for 25-30 minutes. Uncover; bake 5-10 minutes longer or until bubbly.