Do you remember the good old veal in tuna sauce, typical of Piedmont cuisine? That is the inspiration for these meat-balls, ideal as a second course or finger food, depending on the size. Keep a good amount of bread with you, as “scarpetta” is a must with tuna sauce.
In a vessel, soak bread under water, then squeeze when softened. Knead bread with meat, yolk, parmesan, salt and pine nuts. With wet hands, shape balls of your preferred size.
In the meantime, put on the fire a pot containing 2 litres of water and celery, carrot, and onion, bring to boil, add salt, and cook for at least 30 minutes. Soak balls and put them in a bowl when cooked. Cooking time depends on the dimension: they should change color.
Put in a blender all ingredients for the sauce and blend until obtaining a very smooth cream; should it be too dense, add some broth you used to cook the meat-balls. Season and serve meat-balls at room temperature.