• How to make freeze-dried strawberry powder: Add freeze-dried strawberries to a food processor and pulse into a fine powder. If you don't have a food procesoor, place the freeze-dried strawberries in a ziplock bag and use a rolling pin to beat the strawberries until they are powdery. Set aside.
• In a large bowl, add butter. Sift in confectioners' sugar and add vanilla extract. Mix with a spatula or mixer just until combined.
• Sift in the cake flour, freeze-dried strawberry powder, and salt. Mix with a spatula until the dough starts to come together. It will look crumbly at first, but the dough will come together as you continue mixing.
• Chill the dough for at least 30 minutes in the refrigerator.
• Preheat oven to 300℉/150℃ and line two baking pans with parchment paper.
• Take the dough out of the refrigerator. Roll the dough into a 1/4-inch (5 mm) thick slab. Cut the dough with a cookie cutter. Place the cut dough on baking sheets, spaced at least an inch apart. Re-roll the scraps and refrigerate for a few minutes until firm again. Repeat the process until all the dough is used.
• Chill in the refrigerator for another 30 minutes if the dough has warmed up.
• Bake for 15-18 minutes or until the bottom edges of the cookies are lightly brown.
• Let the cookies cool for about 5 minutes on the baking sheet, then carefully transfer them to a wire cooling rack to cool completely.

Decoration

• Pour the melted white chocolate into a piping bag and drizzle the chocolate over the cookies.
• Sprinkle chopped freeze-dried strawberries over the cookies. Let the chocolate firm up before serving.