In a large bowl, mix the veal with the pork, garlic, shallot, salt and nutmeg. Refrigerate for 1 hour. In a bowl, mix cup of the bread crumbs and the milk; let stand for 10 minutes. Transfer to a food processor and work to a paste. Stir the paste, egg yolk and Gruyère into the veal mixture. Roll into 1-inch balls; refrigerate for at least 1 hour.
Put 1/2 cup of the tapioca starch, the beaten eggs and the remaining 1 cup of bread crumbs in 3 bowls. Stir the remaining 3 tablespoons of tapioca starch into the bread crumbs. Dust each meatball in the tapioca. Roll in the eggs, then in the bread crumbs.
In a saucepan, heat 1 1/2 inches of oil to 350°. Fry the meatballs in batches until golden and cooked through, about 4 minutes. Drain on paper towels; serve.