Crockpot Stuffed Shells

1 Pound ground beef
1 Onion, chopped
1 Clove garlic, minced
2 Cups mozzarella cheese, shredded
1/2 Cup seasoned bread crumbs
1 Tablespoon parsley flakes
1 Egg, beaten
20 to 25 Jumbo pasta shells, partially cooked & drained
2 (15 1/2 ounce) Jars meatless spaghetti sauce
1/2 Cup Parmesan cheese
Spinach Stuffing for Shells
1 1/2 Pounds ground beef
2 Cups mozzarella cheese
2 Cups cottage cheese
1 Cup Parmesan cheese
1 Egg
1 (10 ounce) Package frozen spinach, squeezed dry
1 Box partially cooked jumbo shells

Brown ground beef, onion and garlic in skillet, drain. Add cheese, bread crumbs, parsley and egg. Gently stuff shells with beef mixture; set aside. Pour 1/2 jar of sauce into crockpot. Arrange stuffed shells in sauce. Layer sauce and shells ending with sauce. Top with parmesan cheese. Cover and cook on Low 5 to 7 hours.