Biscotti di Prato

Preheat oven to 350 degrees.
Cover a baking sheet with parchment paper.
Sift flour, sugar, one pinch of salt, baking soda and baking powder together three times.
Place in a large mixing bowl and make a well in the center.
Beat three eggs and vanilla together and pour into the middle of the dry ingredients.
Using a rubber spatula, begin to work the flour mixture into the eggs, drawing the dry ingredients from the outside to the center.
The mixture will be crumbly at first, but gradually will form a soft dough.
When the dough cleans the sides of the bowl, allow it to rest a minute or two.
It will soften further.
Transfer dough to a lightly floured surface and flatten to form a rectangle about six by 10 inches.
Scatter almonds over the dough and roll the dough up over the almonds.
Flatten the dough slightly, then cut into three equal portions.
Roll each portion under the palms of your hands to form a cylinder 12 inches long.
Place the three cylinders on the baking sheet.
Beat the remaining egg with a pinch of salt and brush the egg wash over each cylinder.
Bake about 20 minutes, until golden and firm to the touch.
Place cylinders on a cutting board and slice through them at a 45-degree angle at one-half inch intervals.
Remove the parchment paper from the baking sheet.
Place the slices standing up on the baking sheet and return them to the oven for another 15 minutes to dry.
Allow to cool, then store airtight.