What is the best way to keep meatballs moist while cooking?

Since the protein in meat causes it to shrink when cooked and can result in tough meatballs, you should have insurance against that. Eggs and binders, such as breadcrumbs, mixed with milk help keep the meatballs tender and moist, so don't skip any of them. These homemade meatballs can be simmered in tomato sauce and can be served as spaghetti and meatballs or with sauce over mashed potatoes. Baked meatballs For perfectly browned meatballs with an almost crispy crust, cook them in a pan on the stove.