For meatballs, combine sausage, bread crumbs, 1/4 cup cheese, milk, egg, basil, black pepper and garlic salt in large bowl. roll into 1/2" balls.

add pasta, cook on low 30 minutes. stir in spina v

Combine broth, tomato paste, garlic and red pepper flakes in crockpot. add meatballs, cover crockpot. cook on low 5-6 hours.

add pasta; cook on low 30 minutes. stir in spinach when pasta is tender

sprinkle with additional cheese.