01 -
In a medium bowl, whisk together the flour, salt and baking soda until thoroughly combined.
02 -
In the bowl of a stand mixer fitted with the paddle attachment, cream the butter with the sugar on medium speed until pale and fluffy, about 3 minutes.
03 -
Add the egg and egg yolk to the butter mixture, and mix to combine. Add the vanilla and mix until incorporated.
04 -
Add the flour mixture and mix until just combined; reserve the medium bowl. Be careful not to overmix the dough to prevent tough cookies.
05 -
In a food processor or high-speed blender, pulse the freeze-dried berries into a fine powder.
06 -
Divide the dough in half, and transfer one half to the reserved mixing bowl. To the stand mixer bowl containing the remaining dough, add the berry powder and mix on medium speed until just combined.
07 -
Preheat the oven to 350°F (175°C) and line three baking sheets with parchment paper.
08 -
To form each cookie, pinch off a small piece (22g or approximately 1 tablespoon) of each dough variety and lightly press them together, then roll into a ball. Arrange the dough balls between the baking sheets, about 8 per sheet.
09 -
Bake the cookies one baking sheet at a time, until they are puffed and set but not golden on the edges, 9 to 10 minutes.
10 -
Allow cookies to cool on the baking sheet for about 5 minutes before transferring to a wire rack to cool completely.