Spinach Garlic Meatballs Stuffed With Mozzarella

Name: Spinach Garlic Meatballs Stuffed With Mozzarella
Cuisine: European, Italian, Mediterranean
Ingredients: 8 ounces baby spinach (fresh); 3 cloves garlic (finely chopped); 1-2 T. olive oil; 1 pound ground beef; 1 pound ground pork; 2 1/4 c. bread crumbs; 3 eggs (If eggs are small you may need 4); splash of milk; 4 garlic cloves (finely chopped); 1/2 c. Parmesan; salt/pepper; 2 T. olive oil; mozzarella cheese (cut into small cubes); 1 jar Rao's marinara sauce