In the 1780s, several Swiss pastry chefs migrated to Mantua and introduced a whole new world of cakes, now designated PAT. One is the anello di Monaco and another is Elvezia (or Helvezia): consistes of three disks of almond paste, sugar and whipped egg whites, baked in the oven and them stuffed with filled with zabaglione and butter cream.
Image by Massimo Telò, Creative commons License