Breton shortbreads or sablés are very popular in France, and this amusing variation with chunks of milk chocolate was created by one of France’s best-known pastry chefs, Frederic Bau. “Truffled” in recipes usually refers to foods studded with black Périgord truffles, an aromatic fungus, sort of a subterranean mushroom. The chopped chocolate throughout the cylinder of cookie dough makes the roll of dough resembl