Preheat your oven to 200°C (390°F) and line a baking sheet with parchment paper.
In a large mixing bowl, combine the ground beef, panko breadcrumbs, egg, minced garlic, chopped parsley, salt, and pepper. Gently mix everything together until just combined, being careful not to overwork the mixture.
Shape the mixture into small, uniform balls about 1 inch in diameter, placing them evenly on the prepared baking sheet. Keep the meatballs snug but not too tight to maintain tenderness.
Heat a tablespoon of cooking oil in a large skillet over medium heat until shimmering and slightly smoky. Carefully add the meatballs in batches, avoiding overcrowding, and brown them on all sides for about 2-3 minutes per batch, until golden and crispy.
Once browned, transfer the meatballs to the oven and bake for another 10-12 minutes, or until cooked through and juices run clear. The meatballs should be firm yet juicy inside with a crisp exterior.
Remove the meatballs from the oven and let them rest for 5 minutes. Gently spoon shredded mozzarella cheese on top and serve warm with your favorite dipping sauces.