Preheat oven to 350° F or 175° C.
On a piece of parchment paper that fits a half sheet pan, draw lines 4” apart with 1” between each set of lines.
Place the granulated sugar and the lemon zest in the bowl of a stand mixer and with your fingertips massage the lemon zest into te sugar.
Add the eggs to the sugar, and using the whisk attachment, beat for 10 minutes. It will have tripled in volume and be a pale yellow in color.
Remove the bowl from the mixer and sift in the flour and baking powder.
Using a rubber spatula gently fold in the flour.
Place the mixture in a pastry bag with a 1/2” plain tip and pipe the cookies into 4” strips.
Lightly sift powderd sugar over the tops of each cookie. Let the cookies rest for 5 minutes.
After the 5 minutes sprinkle again with powdered sugar and immediately place in your preheated oven on the middle rack of your oven.
Bake for 12 minutes if you would like soft lady fingers.
Bake 16-18 minutes for a crispy ladyfingers that you can use to make Tiramisu.
Remove from oven and place on a wire rack to cool for 5 minutes. Peel them off the parchment paper and place them directly on a rack to cool completely.