To start, preheat your oven to 200 °C (392 °F), and line two baking trays with parchment paper to prevent sticking. Divide the egg whites from the yolks in 2 separate bowls.
Whip the egg whites with 70 g sugar and a pinch of salt using an electric hand mixer or stand mixer, continuing for a few minutes. Don’t stop when the egg whites just become foamy — you need to achieve a glossy, stiff meringue with a consistency similar to very thick whipped cream.
In a separate bowl, whisk the egg yolks until smooth and free of lumps.
Gently fold the egg yolks into the meringue using a spatula, and slowly mixing from bottom up, to maintain the airy texture.
Sift the flour and add it to the mixture in two or three batches. Fold gently to avoid deflating the batter. The result should be a light, fluffy, and well-incorporated batter.
Transfer the batter into a piping bag. Pipe the batter onto the prepared trays in strips about 1.5 cm wide and 8 cm long, or you can use a ladyfinger silicone mold.
Sprinkle the piped batter first with granulated sugar, then sift powdered sugar over the top.
Place the trays in the preheated oven, with a wooden spoon keeping the door slightly open. Bake for about 5 minutes, then dust with more powdered sugar. Continue baking for another 1–2 minutes, or until golden brown. Once baked, remove the trays from the oven and let the cookies cool slightly.
Your Savoiardi are Ready! Use a spatula to carefully peel them off the parchment paper. Optionally, dust with more powdered sugar. The interior should remain soft, surrounded by a crispy sugar crust.