In a medium size bowl, whisk together the flour, cornmeal, black pepper and salt. Set aside.
In a large bowl with a handheld mixer or the bowl of a stand mixer fitted with the paddle attachment, beat the butter, sugar, lemon zest, and lemon extarct on medium-high speed until light and fluffy (about 2-3 minutes). Add the egg yolks and beat again to combine.
Reduce mixer speed to low and add the flour mixture and beat until just blended. Dough will be very crumbly.
Lay out two sheets of plastic wrap.
With floured hands, press dough together and divide in half. Form dough into two 6" long logs and wrap very tightly in each sheet of plastic wrap. Chill in the refrigerator at least 4 hours, preferably overnight.
When you are ready to bake the cookies, preheat the oven to 400ºF. Line two large baking sheets with parchment paper. Do not use silicone baking sheets. Set aside.
Cut cookie logs into 1/4" to 1/2" rounds and bake 11-12 minutes or until edges are just turning golden brown. Allow to cool on baking sheet about 5 minutes before transferring to a wire cooling rack to cool completely. Leftovers stay fresh covered tightly at room temperature up to 1 week. Logs may be frozen, wrapped tightly, up to 3 months. Thaw in refrigerator overnight and proceed with baking as directed.