Preheat oven to 350ºF.
Place meat in a mixing bowl. On a cutting board, combine zest with parsley and 2 cloves of garlic and finely chop together to make a gremolata. Add gremolata and breadcrumbs to the meat along with egg, milk, salt, pepper, 1/4 to 1/3 cup grated cheese and about 2 tablespoons EVOO. Combine meatballs and roll into walnut-sized balls. Arrange on a nonstick baking sheet and roast 15 minutes or until cooked through.
Place a large pot of water on stove to boil for spaghetti.