Preheat oven to 200C / 400F (non fan-assisted). Line a baking dish that can fit the dinner rolls snugly with parchment paper, allowing the sides to extend out so that it's easier to lift out the sliders later on.
Mash the meatballs together and divide into 4 portions. Roll each portion into a ball and flatten into a patty.
Heat oil over medium heat in a frying pan. Add in the meatball patties and cook for 2 to 3 minutes on each side until the meatball patties are cooked. Remove with a slotted spoon and set aside.
Split the dinner rolls in half lengthwise, then place the bottom half in the baking dish. Spread the Mayo Sauce on top, then arrange the meatball patties on top. Sprinkle, cheddar, mozzarella and half of the Parmesan cheese on top. Place the top half of the dinner rolls on top, pressing down slightly.
Brush the top of the dinner rolls with Garlicky Sauce and sprinkle with the rest of the Parmesan cheese.
Bake in the middle rack for 15 to 20 minutes until cheese has melted and the top is golden-brown.
With the help of the parchment paper, lift out the sliders and serve immediately with an ice cold beer.
Stir mayonnaise, tomato paste (or ketchup) and mustard in a small bowl.
Stir melted butter, parsley and garlic together.
- You can use homemade meatballs, store-bought meatballs or real-meat sausages for this recipe - it's up to you!