In a small bowl or pot, pour the warmed milk over oatmeal, mix and set aside to absorb moisture and soften.
Add all the meatball ingredients, including the oatmeal, to a large bowl. Knead with a hand (preferably wearing a disposable glove) until the mixture is well combined and cohesive.
Form meatballs from the mixture. The easiest way to do this is to scoop equal portions with an ice cream scoop, roll them into a ball and place the prepared meatballs on baking paper, where they can wait for their turn to be fried.
Heat some oil and butter in a large frying pan over medium heat. Fry the meatballs in batches, turning them gently so that they are nicely browned on all sides (about 4-5 minutes). Place the fried meatballs on a large plate.