Measure the flour into a medium-sized bowl. Place 1/3 of the flour and the freeze-dried strawberries in a mini food processor and process until the freeze-dried strawberries are completely pulverized. Pour this mixture into the main bowl of all-purpose flour.
If you don’t have a food processor place the freeze-dried strawberries in a zip top freezer bag. Use a rolling pin to beat the strawberries until they are powdery and fine and you don’t see any large pieces. Pour the strawberries into the bowl ith the flour and whisk to combine.
Place the butter, sugar, pure vanilla extract, and salt in the bowl of a stand mixer with the paddle attachment and mix on medium speed until the mixture is smooth and creamy, about 2 minutes. Stop the mixer, scrape down the bowl and paddle attachment.
Add all the flour-strawberry mixture at once. Turn the mixer to low speed and mix until all the dry ingredients are combined and the dough forms into a cohesive dough ball. The dough will be crumbly at first but then form into a dough ball.
Turn the cookie dough out onto a lightly floured surface. You can turn it out onto a large piece Silpat. Use your hands to shape the dough into a rectangle and lightly flour the top of the dough. Do not use too much flour, just enough to keep the rolling pin from sticking.
Roll the dough out to 1/2-inch thick. Use a 2-inch round cookie cutter to cut out the cookies. Place the cookies on a board or small sheet pan lined. Prick each cookie in the center with the tines of a fork. Pricking the cookies will allow the steam from the butter to escape when the cookies bake and ensure the cookies stay flat when baked.
Chill the dough in the refrigerator for at least 20 minutes. Chilling the dough will help the cookies hold their shape when baking. The dough can be refrigerated for to 2 days. If not baking the cookies within 2 hours of refrigerating them, cover them with plastic wrap to keep them from drying out.
While the cookies are chilling preheat the oven to 300 degrees F. Line a half baking sheet with parchment paper. You can also use Silpat, but I noticed when baking these cookies on Silpat the bottom of the cookies tend to flare out as they bake.
Place the cookies on a half baking sheet, 2 inches apart (12 cookies in total). Bake the cookies for 20-23 minutes. The baking time will vary
The goal of baking at 300 degrees F is to bake the cookie without browning it on top, they will have just a little color on the bottom. To check for doneness after 20 minutes, take an offset spatula and gently flip one of the cookies over. If the cookie holds together and there a little bit of browning on the bottom, the cookie is done.
Take the cookies out of the oven and allow them to cool for about 5 minutes on the cookie sheet before moving them to a wire rack to completely cool.
At this point the cookies are ready to eat. If you want to glaze them with a strawberry glaze follow the directions for the strawberry glaze.