Preheat the oven to 425°F. Line a baking sheet with foil then spray it with nonstick cooking spray.
In a medium bowl, mix together beef, parmesan cheese, egg, salt, pepper, garlic powder, and Italian seasoning. Use your hands to mix well if needed.
Scoop approximately 2 tablespoons of the meat then roll it into a ball. Press a cube of cheese into the center of the ball. Surround the cheese with meat and reroll it into a ball. Place the meatballs onto the prepared baking sheet.
Lightly spray the meatballs with cooking spray. Place in the oven for 14-17 minutes until browned and cooked through.
Pour warm marinara sauce over the meatballs then sprinkle with parmesan cheese and fresh parsley. Serve.
Store leftover meatballs in an airtight container in the refrigerator for up to 1 week.