In a large bowl, whisk together milk and eggs until combined. Add ground beef, Italian sausage, breadcrumbs, Parmesan cheese, salt, pepper and garlic powder mix together until well combined.
Heat broiler to high; place an oven rack about 4 to 5 inches from the broiler. Lightly grease 2 baking sheets with cooking spray or oil. Using your hands, shape (about 40) 1 to 2-inch meatballs from the mixture; place on prepared baking sheets.
Broil meatballs 6 to 8 minutes, flipping halfway through, until browned.
At this point you can cool, bag, and freeze for a later day or transfer to a 6-quart slow cooker.
Top meatballs evenly with sauce. Cover and cook on low 4 to 5 hours in the slow cooker until meatballs are cooked through to an internal temperature of at least 160 degrees F.
Serve with pasta, on a sub roll, or as an appetizer!
*This recipe makes a lot of meatballs. Plan on freezing some, or cut the recipe in half.Gluten Free
Use a Gluten Free bread crumb. I use crushed seasoned rice chex.Dairy Free
Use a dairy free milk alternative and omit the Parmesan cheese.