1. Peel and cut sweetpotatoes in small pieces and boil them in salted water for approx. 10 minutes. Filter the water and press sweetpotatoes through a potato ricer into a big stirring pan. Let the mashed potatoes cool. Next, grease the hollows of the Madeleines pan and dust them with flour. Then separate the eggs and whisk the egg whites.
2. Add butter, orange peel and sugar to the mashed sweetpotatoes. Mix everything with the whisk of the hand mixer until creamy. Add the egg yolks one after the other and stir in well. Mix flour and baking powder, add and stir in briefly. First stir in a third of the egg whites, then carefully pour in the rest.
3. Fill the dough into a piping bag with a large perforated spout. Spray into the hollows of the Madeleines pan. Bake in a preheated oven at 200 °C (convection oven: 180 °C) for 10-12 minutes. Take out, remove the Madeleines from the pan. Wash the pan, grease and flour again and fill in the rest of the dough and bake again.
4. Let the Madeleines cool on a grack. Dust with powdered sugar and serve (preferably fresh).
Preparation time: approx. 1 hour (without waiting time)