01 -
Set oven temperature to 375°F (190°C) and allow to preheat fully.
02 -
Lightly grease a medium baking dish and arrange the fully cooked meatballs in an even layer across the base.
03 -
Pour the brown gravy evenly over the meatballs and gently stir to ensure all meatballs are well coated.
04 -
Carefully spoon mashed potatoes over the meatball and gravy mixture, using a spatula to level the surface smoothly.
05 -
Generously sprinkle shredded mozzarella or cheddar cheese over the mashed potato layer.
06 -
Place in the oven and bake uncovered for 25 to 30 minutes, until the cheese turns golden and the mixture bubbles around the edges.
07 -
Remove from the oven and allow to rest for several minutes before serving. Garnish with chopped parsley or green onions, if desired.