Beat egg whites with an electric mixer fitted with the whisk attachment until foamy. Gradually add sugar and almond extract, continuing to beat until very stiff peaks form. Switch to the paddle attachment and mix in almond meal until dough comes together.
Cover cookie dough with plastic wrap and refrigerate, 3 hours to overnight.
Preheat oven to 325 degrees F (165 degrees C). Line baking sheets with parchment paper.
Pour confectioners' sugar into a shallow bowl. Roll cookie dough into small balls and coat with confectioners' sugar. Arrange on the baking sheets.
Bake cookies in the preheated oven until lightly browned and firm, 10 to 15 minutes.