Seaweed Shortbread

Directions

1. 1
   Preheat the oven to 300.
2. 2
   Grease a 9-inch-square baking pan and line with parchment paper, leaving a few inches of overhang at 2 ends.
3. 3
   Line a rimmed baking sheet with parchment paper.
4. 4
   In a medium bowl, whisk the 2 flours with the kosher salt.
5. 5
   Place the seaweed in a small resealable plastic bag and lightly crush with a rolling pin.
6. 6
   Whisk 1/2 cup of the crushed seaweed into the dry ingredients.
7. 7
   In a large bowl, using a hand mixer, beat the butter at moderately high speed until light and fluffy, about 2 minutes.
8. 8
   Add the 1/2 cup of sugar and beat until the mixture is smooth and pale yellow, scraping down the side of the bowl as needed, about 2 minutes more.
9. 9
   Beat in the dry ingredients; the mixture will resemble wet sand and hold together when pressed.
10. 10
    Transfer the dough to the prepared pan and pat into an even layer.
11. 11
    Bake for about 1 hour and 20 minutes, or until the shortbread is a light golden brown.
12. 12
    Let cool on a rack for 5 minutes.
13. 13
    Using the parchment overhang, transfer the shortbread to a work surface.
14. 14
    Brush the top with the egg wash and sprinkle with sugar, flaky sea salt and the remaining 3 tablespoons of crushed seaweed.
15. 15
    Cut the shortbread square into thirds, then slice crosswise into 3/4-inch-wide cookies.
16. 16
    Transfer to the prepared baking sheet and bake until golden brown on top, about 10 minutes.
17. 17
    Transfer the cookies to a rack and let cool completely before serving.