coconut-citrus thumbprint cookies

Traditional thumbprints get a hint of citrus in these easy-to-make cookies. Perfect to make and give for the holidays, and especially fun to make if you have little hands to help in the kitchen.

1 stick unsalted butter, at room temperature
1/2 cup sugar
1 large egg, separated
Zest from 1/2 lemon
Zest from 1/4 grapefruit
1 teaspoon vanilla extract
Pinch kosher salt
1 cup flour, plus extra for dusting
1/2 cup sweetened flaked coconut
Grapefruit curd, for filling

  1. Using a standing mixer fitted with paddle attachment, cream butter and sugar until combined. Add egg yolk, lemon and grapefruit zest, and vanilla and mix until just combined. Add salt. Slowly incorporate flour, a little at a time, until combined. Transfer dough to a floured board and roll into a flat disk. Wrap in plastic and chill for 30 minutes.
  2. Preheat oven to 350°F. Line a baking sheet with parchment paper.
  3. Whisk reserved egg white with 1 tablespoon water.
  4. Spread coconut out onto a large plate.
  5. Roll dough into 1-inch round balls. Dip each one in egg wash, then roll in coconut. Place on prepared baking sheet. Make a light indentation into center of each cookie with your finger.Bake for about 15 minutes or until edges are just slightly brown. 
  6. Remove pan from oven. Gently press down in center of cookies if necessary to deepen indentation. Spoon in a small amount of curd. Return to oven and bake another 5 minutes, until curd is just set. Allow cookies to cool on baking sheet for 5 minutes. Transfer to a wire rack to cool completely.

Makes approximately 16 cookies.