Prepare the meatballs by making a mix with the pork/veal mince, the eggs, the parmesan, a little milk, two tbsp of breadcrumbs, salt, pepper, nutmeg and the small cubes of Prosciutto Cotto.
Form the mix into medium-sized meatballs and fry them in lots of hot oil.
Cut the red onion into thin slices and grill them together with the slices of speck.
Put the meatballs, onion and grilled speck onto skewers, alternating the ingredients.
Serve the skewers on a slice of toasted rustic bread, along with a hot tomato ketchup.