Meatballs: In a large bowl combine beef, egg, bread crumbs, onion, milk, garlic, salt, pepper & mustard. Mix well using hands. Shape into very tiny meatballs. Heat oil in large skillet, and brown meatballs on several sides. Remove from skillet and place on a large platter or bowl. BBQ Sauce: In a small bowl combine sauce ingredients. Mix well. Pour into a large saucepan. Simmer for 15 minutes to blend flavors. Add meatballs to the sauce and stir gently. Bring to a boil. Reduce heat to low and simmer until meatballs are hot all the way through. Serve in a corningware dish, or a crockpot if it's for a potluck.