Preheat oven to 375 degrees F.
In a mixing bowl fitted with a paddle attachment, stir together the dry ingredients.
In a small bowl, whisk together the eggs and the yolks. Add them to the dry ingredients and mix on low until moistened and combined.
Flour your hands slightly and roll the dough into log 2-inches in diameter. Place on a sheet pan and brush with the beaten egg white. Sprinkle with sugar and bake until golden brown, about 10-15 to minutes. Lower oven temperature to 325 degrees F.
Let cool for 5 minutes, then, cut on a bias with a serrated knife. Lay the slices out on a sheet pan and return them to the oven to dry out. Let cool, then store in an airtight container. Dip in Vin Santo.
Recipe courtesy of Michael Chiarello