For the cheese filling, add all ingredients to a food processor and puree until well combined. Scoop the filling out into 12 (1-tablespoon) balls. Cover and freeze until solid, about 2 hours.

Meanwhile, mix together all ingredients for the meat in a large bowl. Scoop the meat into 12 equal portions and roll each into a ball. Cover and refrigerate until the cheese balls are frozen.

Once the cheese balls are frozen, preheat the oven to 375F and line a large baking sheet with foil or parchment paper. Lightly spray it with avocado oil.

Working with 1 meatball at a time, stuff a cheese ball into the center and shape the meat around the cheese. Continue until all the meatballs are stuffed with cheese.

Arrange the meatballs on the prepared baking sheet and lightly spray the tops with avocado oil. Bake until the meat is cooked through, about 20 minutes.

Serve warm, with marinara sauce if desired.