01 -
Spray a baking sheet with non-stick cooking spray. Preheat the oven to 400 degrees Fahrenheit.
02 -
Place the cooked or frozen meatballs in a large pot. Cover them with pasta sauce. Heat the mixture on low-medium heat, stirring occasionally, until the meatballs are warmed thoroughly.
03 -
Fill each sandwich roll with approximately 4-5 meatballs, depending on the size of the rolls and meatballs. Add extra pasta sauce on top of the meatballs. Arrange the filled rolls closely together on the prepared baking sheet.
04 -
Sprinkle shredded mozzarella cheese on top of each sandwich. Bake in the preheated oven until the cheese is melted, hot, and bubbly.