Prepare the Meatballs: Preheat oven to 375°F (190°C). In a bowl, combine ground beef, breadcrumbs, egg, garlic powder, onion powder, salt, and pepper. Shape into 1-inch meatballs and place on a lined baking sheet.
Bake the Meatballs: Bake for 20-25 minutes, or until cooked through.
Make the Glaze: In a saucepan, combine Dr. Pepper, ketchup, brown sugar, and Worcestershire sauce. Simmer for 15-20 minutes until thickened.
Glaze the Meatballs: Toss baked meatballs in the glaze, then return to the oven for 5-10 minutes to caramelize.
Serve: Garnish with parsley or green onions if desired, and serve hot.