In a medium bowl, combine flour, almond flour, baking powder, and salt, Whisk well and set aside.
In a large bowl use an electric mixer (either a hand mixer or stand mixer will work), and add the softened butter and granulated sugar. Beat on high for 30 seconds to 1 minute until well combined, lightened in color and slightly fluffly.
Add the egg and a teaspoon almond extract to the butter mixture. Continue beating at a medium speed until the egg is full incorporated, it will be pretty thin and liquidy.
Add the dry ingredients into the wet ingredients gradually, about ½ cup to 1 cup at a time. Using your mixer, beat on low between each addition.
Wrap the almond cookie dough in plastic wrap and chill in the refrigerator for at least 2 hours or up to overnight.
While dough is chilling, preheat the oven to 375 degrees. Line the cookie sheets with parchment paper or silicone mats.
Using dough sticks or a rolling pin with measuring sides, roll out the dough to ¼" to 5/16t" inches. It is easiest to roll out the dough between two sheets of wax paper.
Cut out your shapes and place at least one inch apart on lined baking sheet. Bake for 10-12 minutes.
Allow cookies to cool on the tray for at least 5 minutes and then transfer them to a cooling rack.
Decorate with royal icing, frosting, or almond frosting.
Notes
Storage: Store cookies in an airtight container for up to 1 week. Store them in the freezer in an airtight container for up to 3 months.