Preheat the oven to 425 degrees F/220 degrees C. Using a pastry brush, butter the cavities of the metal madeleine pan. Then dust it with flour, and tap any excess flour; there is no need to grease a silicone mold. Using a piping bag, fill the cavities up to ¾ (photo 7). Bake at 425 °F/220 °C for 3 minutes.
https://www.bakinglikeachef.com/madeleines-by-lecole-de-cuisine-dalain-ducasse/

