Pull the butter from the refrigerator 2 hours before you mix the dough.
Using a rolling pin, smash up the freeze-dried strawberries, keeping them in the bag helps keep them all together.
Add the butter, the brown sugar, white sugar, and salt to the mixing bowl of a stand mixer fitted with the paddle attachment. You can use a handheld mixer fitted with the dough attachments, and a separate mixing bowl.
Cream the butter, sugars, and salt together on medium-high speed. Scrape down the bowl with a rubber spatula and mix again until well combined.
Add the flour one cup at a time, mixing on low to medium speed until combined, scraping down the bowl with a rubber spatula in between.
Add the crushed freeze-dried strawberries and mix on low to combine.
Place a piece of parchment paper on a board or countertop, scrape out the dough onto it. Using your hands push the dough together forming a flat rectangle.
Wrap the dough tightly in the parchment paper and plastic wrap. For the best results allow the dough to chill in the refrigerator overnight or for at least 4 hours.
When the dough is chilled, lightly flour a cutting board or countertop. Remove the dough from the wrappings and place it on the floured surface. Allow it to sit for about 20 minutes before rolling it out.
Roll the dough out to about ½ inch thickness, being careful to not let it stick to the board. If you need to release it from sticking use a dough blade or the flat side of a knife to shimmy under it to release it. Shortbread dough can be a bit crumbly, that's normal, just use your hands to push it back together as you roll it out.
Using the cutters of your choice, cut out the tops and bottoms of your sandwich cookies. First cut a large sized cookie then use a smaller cutter to create the window.
Make sure to cut an equal number of tops and bottoms for your sandwich cookies. Place them carefully onto a prepared baking sheet pan, and into the freezer for 30 minutes while you preheat the oven to 350℉
Separate the cut cookies onto 2 baking sheet pans lined with parchment paper, Spacing them about 2 inches apart. Bake at 350℉ for 4 minutes then rotate your pans and continue baking for 5 minutes. Place the pans on a wire rack to cool.
Cool to room temperature and spread the jam on the bottom cookie, place the cut-out cookie on top and garnish with reserved crushed strawberries and powdered sugar.
Always keep in mind that you can push together the leftover scrapes from cutting out the cookies and wrap it tight with plastic wrap and either refrigerate or freeze to bake at another time. Make sure you at least refrigerate it for 4 hours before rolling and baking.
