Preheat the oven to 350 degrees F.
In a large bowl or mixer, thoroughly mix the beef, pork, breadcrumbs, milk, parsley, eggs, garlic, onion and some salt and pepper. Chill in the refrigerator for 30 minutes.
Shape into meatballs and place on a foil-lined shallow baking pan. Bake 30 minutes for medium or 25 minutes for bite-size. Stick toothpicks in the finished meatballs to serve as an appetizer.