Line 2 baking sheets with parchment paper. Preheat oven to 350 degrees.

Sift together flour, baking powder, and salt.

Separate eggs, adding the whites to the bowl of your mixer and the yolks to a separate bowl.

Whisk together egg yolks and granulated sugar until light and pale. Set aside.

Beat egg whites and cream of tartar until stiff peaks form, but do not overbeat.

Fold in half the stiffly beaten egg whites to the egg yolk mixture, until just combined.

Add the flour mixture to the egg mixture and fold until fully incorporated.

Fold in the remaining egg whites, again folding until just combined in order to not break down the air in the whites.

Pipe 3- by 1-inch fingers, leaving an inch between each one on lined pan.

Generously dust with powdered sugar, and bake until puffed and edges and bottoms begin to brown, about 12-15 minutes.

Let cool completely before storing in an airtight container for up to 2 weeks.

Eat as is or use in your favorite Tiramisu recipe.