- 3 eggs, separated, at room temperature
- 1/2 cup granulated sugar
- 1/2 cup unbleached all-purpose flour, sifted
- 2 Tbs. Dutch process cocoa powder
- Confectioners' sugar for dusting
Draw 2 pairs of lines, spacing each pair 3 inches apart (almost the height of an 8-cup charlotte mold), down the length of a piece of parchment paper large enough to fit on a 12-by-18-by-1-inch baking sheet. You should have 4 lines. Put the paper, marked side down, on a baking sheet.
Using a stand mixer fitted with the whisk attachment, beat the egg whites on medium speed until they start to foam. Add one-third of the granulated sugar and beat until the whites are opaque, then add another third of the sugar. When the whites start to increase in volume and become firm, add the remaining sugar and increase the speed to high. Beat until the whites form soft peaks but still look wet.
In a bowl, whisk the yolks by hand until blended. Using a large rubber spatula, carefully fold the yolks into the beaten whites. In a sifter, combine the flour and cocoa powder. Sift half of the flour mixture over the egg mixture and carefully fold in. Repeat with the remaining flour.
Fill a pastry bag fitted with a 3⁄4-inch plain tip with the batter. Pipe 3-inch strips of batter, with the edges just barely touching, between each set of lines on the parchment paper. You should have about 20 ladyfingers. The ladyfingers will spread as they bake and adhere together, but still retain their individual shapes. Using a fine-mesh sieve, dust the strips with a fine layer of confectioners' sugar.
Bake until the batter is puffed, lightly browned and slightly cracked, 10 to 12 minutes. Transfer the sheet to a wire rack and let the ladyfingers cool completely.