A hearty sandwich with homemade meatballs bathed in marinara, nestled into a garlicky toasted bun, and topped with melted cheese, is perfect for dinner or game day.
Preheat oven broiler to high. LIne a baking sheet with foil or parchment paper for easy cleanup.
Place meatballs in a large saucepan and add a full jar (or 3 cups) of marinara sauce. Bring to a simmer over low heat until meatballs and sauce are heated through. (This will take a bit longer if using frozen meatballs, but they don’t need to be defrosted first.)
Meanwhile, combine melted butter and garlic salt in a small bowl. Slice buns along the side and gently open, being careful that the bun stays intact. Place buns on a baking sheet. Brush open face of the buns with the butter mixture. Coat well (you may not use all of the butter). Place in the oven and broil for 2 to 3 minutes or just until bread begins to toast. Remember that the edges of the buns will brown further during the next steps. Remove buns from oven.
Fill each bun with three warmed meatballs, spooning a bit of the sauce over the top. Top each sub with ¼ to ½ cup shredded cheese. Put the filled subs back on the baking sheet.
Broil the subs for 2 to 3 minutes, or just until cheese is melted. Watch closely, and remove the subs from the oven as soon as the cheese is melted.
Serve meatball subs hot, sprinkled with a bit of freshly chopped parsley, and with extra sauce on the side. Makes 4 sandwiches.