In a bowl, whisk together flour, baking powder and cornstarch. Set aside
Using a stand mixer or hand mixer, cream together the butter and sugar until light and fluffy
Add egg and vanilla and almond extracts and continue beating until all incorporated
On low speed, slowly add the flour mixture in three batches, beating until just combined, scraping don the sides between additions. Do not over beat
The dough will be crumbly. Using your hands knead the dough into a ball.
Using only half the dough, roll to ¼ inch thickness on floured surface.
Cut into shapes using floured cookie cutters. Place on parchment paper lined cookie sheet.
Place entire cookie sheet in the freezer for 10 minutes
Preheat oven to 350°F
Transfer cookies from freezer straight into the preheated oven
Bake for 9 -10 minutes for large cookies and 7-8 minutes for smaller cookies. (watch your first batch of cookies closely to get the timing right for the size of cookies you are making)
Let cool on baking sheet for 2 minutes before transferring to cooling racks to cool completely
Store at room temperature in air tight container