Garlic Bread Meatball Sliders

Preheat your oven to 400 degrees Fahrenheit (200 degrees Celsius).

Heat a small amount of olive oil in a saucepan over medium heat. Add an onion and two cloves of garlic; cook and stir until the onion is soft, approximately 5 minutes.

Combine ground beef in a large container. Add the cooked onion-garlic mixture, chopped parsley, an egg, breadcrumbs, and a generous amount of fontina cheese; reserve the remaining cheese for topping. Season with salt, pepper, and a pinch of heat from cayenne. Mix the ingredients together using your hands until they are just combined. Fill each of 24 mini muffin cups with the meat mixture; it's not necessary for them to be perfectly round.

Place the filled muffin cups in the preheated oven and bake until they are no longer pink in the centers, around 12 minutes. Leave the oven on and let the meatballs cool for a short while before preparing the garlic butter.

Melt butter in a saucepan over medium heat. Add any remaining minced garlic once the butter starts to bubble; stir and then remove from heat immediately. Stir well and set aside.

Line a baking sheet with aluminum foil; coat the foil with any remaining olive oil. Transfer the rolls, still attached to their stems, to the baking sheet. Cut a hole in the top of each roll, about two-thirds of the way down. Brush the garlic butter over the insides and outsides of the rolls.

Bake until golden brown, approximately 8 minutes. Pour a small amount of tomato sauce into each hole. Place a meatball inside each hole. Top each roll with a spoonful of tomato sauce and the remaining fontina cheese. Sprinkle Parmesan cheese on top.

Continue baking until the cheese is melted, taking around 12 to 15 minutes. Garnish with additional parsley. Let the rolls sit for a few minutes to firm up; transfer them to a serving platter.