Preheat oven to 325 degrees F (160 degrees C). Place meatballs in a casserole dish.
Bake in preheated oven until warmed through, about 10 minutes.
Combine ketchup, brown sugar, vinegar, Worcestershire sauce, mustard, cloves, garlic salt, and beef bouillon cube in a saucepan; bring to a boil, stirring often. Reduce heat to low and simmer for 5 minutes. Pour sauce over meatballs; cover dish with aluminum foil.
Continue baking in oven until meatballs are hot, about 20 minutes.
Holiday Buffet Meatballs · Dinner Match Lab | Dinner Match Lab