Whisk the egg yolks with half the sugar and the vanilla and continue whisking by hand, either with a hand mixer set at medium speed or in a heavy-duty mixer fitted with the whip, until very light and lemon-colored, about 5 minutes.
In a clean, dry bowl, whisk the egg whites with the salt and whip with a hand mixer or heavy-duty mixer fitted with the whip until they hold a soft peak. Increase the speed to maximum and whip in the remaining sugar in a slow stream. By this time the egg whites should be holding a soft, shiny peak. Remove from the mixer and fold in the yolk mixture.
Sift the flour over the egg mixture and fold in with a rubber spatula, cutting down to the bottom of the bowl to make sure the flour mixes in evenly.
Fill the pastry bag with half the batter and pipe
Bake the savoiardi at 375 degrees for about 15 minutes, until golden and firm to the touch. Remove them, still on the paper, from the pans and place on racks to cool. After cooling, remove the savoiardi from the paper and store in a tin between layers of wax paper.
Granulated sugar for finishing (optional)
© 1990 Nick Malgieri. All rights reserved.