Form the Meatballs: In a large mixing bowl, combine the chicken mince, Panko breadcrumbs, 50g of Parmesan, beaten egg, 2 minced garlic cloves, chopped parsley, oregano, salt, and pepper. Gently mix with your hands until just combined. Be careful not to overmix, as this can make the meatballs tough. I find that using a small ice cream scoop gives you perfectly uniform meatballs every time. Roll the mixture into approximately 16 meatballs.

Brown the Meatballs: Heat the olive oil in a large, heavy-bottomed frying pan or skillet over a medium-high heat. Carefully place the meatballs in the pan, ensuring not to overcrowd it (work in batches if necessary). Cook for 5-7 minutes, turning occasionally, until they are golden brown on all sides. They don't need to be cooked through at this stage. Remove the meatballs from the pan and set them aside on a plate.

Start the Alfredo Sauce: Reduce the heat to medium. In the same pan (don't wipe it out!), add the 60g of butter. Once melted, add the 3 minced garlic cloves and cook for about 1 minute until fragrant, scraping up any browned bits from the bottom of the pan with a wooden spoon.

Build the Creamy Sauce: Pour in the double cream and whole milk, whisking to combine. Bring the mixture to a gentle simmer and let it cook for 3-4 minutes, stirring occasionally, until it starts to thicken slightly.

Finish the Sauce and Simmer: Reduce the heat to low. Gradually stir in the 80g of grated Parmesan cheese until it's completely melted and the sauce is smooth. Season with the grated nutmeg, salt, and pepper to your taste. Return the browned meatballs to the pan, nestling them into the sauce. Let them simmer gently in the sauce for 8-10 minutes, or until they are cooked through.

Prepare the Subs: While the meatballs are simmering, preheat your oven grill to a medium-high setting. Slice your sub rolls horizontally, but not all the way through, creating a hinge. Place them on a baking tray and lightly toast them under the grill for 1-2 minutes until just golden. This step is key to preventing a soggy bottom.

Assemble and Grill: Spoon 4 meatballs and a generous amount of Alfredo sauce into each toasted roll. Top each sub with a handful of grated mozzarella cheese. Place the assembled subs back on the baking tray.

Final Melt: Place the tray under the preheated grill for 2-3 minutes, or until the mozzarella is completely melted, bubbling, and just beginning to turn golden brown. Keep a close eye on them to prevent burning.

Serve Immediately: Garnish with a sprinkle of fresh parsley and serve your Chicken Alfredo Meatball Subs straight away while they're hot and the cheese is wonderfully stretchy.