Ingredients
1 cup all-purpose flour
1/2 cup unsalted butter, at room temperature
2/3 cup confectioners' sugar
4 large egg whites, at room temperature
Preparation
Sift flour into a mixing bowl, and set aside.
In the bowl of an electric mixer fitted with the paddle attachment, beat butter and sugar on medium speed, until well-combined, about 2 minutes. Beat in egg whites, one at a time, beating for 4 minutes after each addition. Add the reserved flour, and mix until just combined.
Reserve 1/2 cup batter; place in a pastry bag fitted with a #2 tip, and set aside for piping chocolate tuile cookies.
