Preheat oven to 350 degrees F.
In the bowl of a stand mixer with the paddle attachment, add the flours, sugar, butter, lemon zest and a pinch of salt. Mix on medium speed until the dough starts to form. Add the 4 egg yolks, 1 at a time, and mix briefly, just to incorporate. Spoon the dough onto a piece of parchment paper and roll into a log shape. Let the dough rest in the refrigerator for 30 minutes.
Unroll dough from parchment paper and slice into half-inch thick cookie rounds. Place the rounds onto an un-greased cookie sheet and sprinkle with the finely chopped almonds. Bake for 10 to 12 minutes. The cookies should be set and light golden brown.
Recipe courtesy of Michael Chiarello, 2007