Using stand mixer with whisk attachment, whip eggs on high speed until yellow, frothy and doubled in volume. This takes about 5 minutes.
Slowly add powdered sugar a bit a time, keeping the mixer going and combining well between additions.
Add the extract of your choice.
Switch out the whisk attachment on your mixer for the paddle and begin adding flour while the speed is on low.
When flour is incorporated turn off mixer and gather dough together and put in a bowl. If your dough is sticky dust with extra flour to help handle the dough.
Cover the bowl with plastic wrap and let the dough sit for a while (1/2 hr to 1 hr).
On a heavily floured surface roll out dough about 1/4-1/2 in. thick and begin pressing mold on dough and creating imprints. Below you will find tips for doing this successfully.
Lay the freshly cut cookies on parchment lined cookie sheets and let dry overnight uncovered. If your cookies are small or your climate is dry this process may take only 6-8 hours.
The cookies are ready to bake when dry on top and starting to dry underneath, but are still mostly moist. You can see a distinction between where the dough is wet and where it is dry.
Bake on the bottom rack in oven at 300 degrees for 10-20 minutes (the size of your cookie will determine this. Cookies are done when they just start to brown around the edges. My small ones take 10 minutes.