Sift flours, sugar, a pinch of salt, baking soda and baking powder together three times. Place in a large bowl and make a depression in the center.

Beat three eggs, vanilla extract (also almond extract, if used) and lemon zest 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. When the dough cleans the sides of the bowl, allow it to rest a minute or two.

Transfer dough to a parchment paper and flatten to form a rectangle about 6 by 10 inches. Scatter almonds over the dough and roll the dough up over the almonds with the help of the parchment paper. 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 a baking sheet lined with the parchment paper and flatten them.

Beat the remaining egg with a pinch of salt and brush the egg wash over each log. Bake about 20 minutes, until golden and firm to the touch.

Place cylinders on a cutting board and slice with your best serrated knife through them at a 45-degree angle at 0.5-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.