Preheat oven to 375°F (190°C). Line 2 baking pans with parchment paper.

In a small bowl, sift together flour and cornstarch.

In the bowl of a stand mixer fitted with the whisk attachment, beat egg whites at medium speed until foamy, about 30 seconds. With mixer on medium speed, add ¼ cup (50 grams) granulated sugar in a slow, steady stream, beating until stiff peaks form, 1½ to 2 minutes. Transfer to a medium bowl.

Clean bowl of stand mixer and whisk attachment. Using the whisk attachment, beat egg yolks and ¼ cup (50 grams) granulated sugar at medium-high speed until pale yellow and thick, about 2 minutes. Using a balloon whisk, fold half of egg white mixture and vanilla into egg yolk mixture just until combined; fold in remaining egg white mixture. Fold in sifted flour mixture in 2 additions just until combined.

Working in batches if necessary, place batter in a large pastry bag fitted with a 7/16-inch round piping tip (Ateco #805). Pipe 3-inch-long lines at least 1 inch apart on prepared pans. (Final dimensions of Ladyfingers should be 3x1 inches.)

In a small bowl, whisk together confectioners’ sugar and remaining 2 tablespoons (24 grams) granulated sugar. Using a fine-mesh sieve, lightly dust piped batter with sugars.

Bake* for 6 minutes. Rotate pans between racks, and bake until lightly golden brown and dry, 4 to 6 minutes more. Let cool completely. Best used within 24 hours.