Such a fun and easy meatloaf recipe! I love the way the mozzarella oozes out of the muffin tin meatloaf!
Preheat oven to 350. Lightly grease a muffin tin and set aside. Chop the onion and cube the mozzarella.
Add egg, milk, ketchup, Panko, and Worcestershire into a large bowl. Add in beef and chopped onion. Season with salt and pepper.
Stir until evenly combined.
Roll a small amount of the meat mixture into a ball. Place 2 or 3 cubes (depending on size) of mozzarella into the mixture. Cover with an equal amount of meat mixture and roll into a ball.
Place into the prepared muffin tin and bake for 25-35 minutes, or until baked through.