The recipe in Martha Stewart's Wedding Cakes book is:
2cups finely ground blanched almonds
1 cup superfine sugar
1 1/2 cups confectioner's sugar
8 large egg whites
1) preheat oven to 200 F. Draw circles on parchment paper the size of your cake. Spray baking sheet with cooking spray. Turn the parchment over so the drawings are facing down, and place on baking sheets. Set aside.
2) Whisk together the almonds, 1/2 cup of the superfine sugar, and the confectioner's sugar; set aside. In the very clean bowl of an electric mixer fitter with the whisk attachment, beat the egg whites until they form soft peaks. One tablespoon at a time, slowly add the remaining 1/2 cup superfine sugar; continue to beat until the mixture forms stiff peaks. Fold in the nut mixture. Spread the mixture inside the circles on the prepared baking sheets to a thickness of 1/2 inch. (I find it easiest to put the mixture in a piping bag without a tip and fill circle in spiral fashion).
3) Bake the dacquoise for 2 hours; turn off the oven and leave inside until completely cooled, about 30 minutes. Wrap each piece individually in plastic wrap, and set aside until ready to use.