01 -
Set oven temperature to 190°C (375°F).
02 -
In a large bowl, combine ground beef, chopped spinach, minced garlic, breadcrumbs, egg, grated Parmesan, salt, and black pepper. Mix carefully without overworking.
03 -
Take portions of the mixture, flatten each, place a mozzarella cube in the center, then shape into smooth balls. Repeat until all mixture is used.
04 -
Heat olive oil in a skillet over medium heat and brown the meatballs on all sides, approximately 5 to 6 minutes.
05 -
Transfer the seared meatballs to a baking dish and cook in the preheated oven for 10 to 12 minutes until an internal temperature of 71°C (160°F) is reached.
06 -
Plate meatballs and optionally top with marinara sauce. Garnish with extra Parmesan or fresh basil if desired.