01 -
Set your oven to 375°F (190°C) and let it warm up.
02 -
Toss ground beef, spinach, garlic, breadcrumbs, egg, parmesan, salt, and pepper into a big bowl and mix until it's just combined.
03 -
Scoop some of the mixture, flatten it, and tuck a mozzarella cube in the middle. Roll it into a ball and repeat with the rest.
04 -
Warm up olive oil in a pan, then brown the meatballs for about 5-6 minutes, flipping to get all sides.
05 -
Move the meatballs into a baking dish and cook them in the oven for 10-12 minutes until they're done.
06 -
Dish them up with marinara sauce on top and sprinkle with fresh basil or parmesan if you'd like.