In a large skillet, combine the jellied cranberry sauce, chili sauce, brown sugar, garlic powder, and black pepper. Cook over medium heat for about 5 minutes, stirring occasionally, until the mixture is smooth and bubbling.

Carefully add the frozen pre-cooked meatballs into the skillet, then gently stir to ensure they are evenly coated with the luscious cranberry sauce. Reduce the heat to medium-low, cover the skillet, and simmer for 15 to 20 minutes.

Once the meatballs are piping hot, transfer them to a serving bowl or slow cooker to keep warm. Optionally, garnish them with chopped parsley or rosemary.