1. Preheat oven to 350 degrees F and cover 2 large cookie sheets with aluminum foil. Grease a 9 x 13 or 7 1/2 x 11 inch casserole dish.
2. In a large bowl, mix together all meatball ingredients. You’ll need to squish the mixture through your fingers to fully combine it.
3. Use a cookie dough scoop to scoop out balls of meat and place them on the cookie sheets.
4. Bake for 20 minutes until browned and firm. Remove the meatballs from the oven and increase heat to 400 degrees F.
5. Use a spoon to carefully remove the meatballs from the released fat and add the meatballs to the casserole dish. If you use the larger casserole dish, you should have one layer of meatballs, and if you use a smaller dish, you’ll have two layers.
6. Pour marinara sauce over the meatballs.
7. Sprinkle mozzarella cheese on top.
8. Bake for 5-10 minutes until cheese is melted and sauce is bubbling.
9. Serve immediately.