Creating these Spinach Garlic Meatballs Stuffed with Mozzarella is straightforward when you follow these simple steps:

1. Preheat Oven: Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper or lightly grease it.
2. Mix Ingredients: In a large mixing bowl, combine the ground beef or turkey, chopped spinach, minced garlic, breadcrumbs, egg, salt, black pepper, and Italian seasoning. Mix until just combined; do not over-mix to maintain tenderness.
3. Prepare Stuffing: Take a small amount of the meat mixture, flatten it in your palm, and add a tablespoon of shredded mozzarella cheese in the center. Encapsulate the cheese by rolling the meatball into a round shape, ensuring the cheese is fully enclosed. Repeat this for the remaining mixture.
4. Place on Baking Sheet: Arrange the stuffed meatballs on the prepared baking sheet, leaving some space between each one for even cooking.
5. Bake the Meatballs: Bake in the preheated oven for 25-30 minutes or until golden brown and the internal temperature reaches 160°F (70°C).
6. Optional Frying: Alternatively, you can fry the meatballs. In a large skillet, heat olive oil over medium heat and cook the meatballs until browned on all sides and cooked through.
7. Serve: Once cooked, allow them to cool slightly before serving. Consider garnishing with fresh herbs or additional cheese.

Following these straightforward steps will help you create delicious Spinach Garlic Meatballs Stuffed with Mozzarella that everyone will enjoy!