Combine ground chuck, Pet Milk, onion, garlic salt and bread crumbs in a bowl. Using a medium cookie scoop, place meat balls on a parchment lined cookie sheet and bake in a 425 degree F oven for 20 minutes.
Combine cheese sauce ingredients in a sauce pan and simmer until smooth and all ingredients are combined. Place baked meatballs in a chafing dish and add sauce, lightly tossing until all of the meatballs are coated.
Hint: The meatballs can be prepared and baked a day ahead of time and then refrigerated. Reheat the meatballs in the microwave and then add the prepared sauce just before serving.