Blanch eggs with white sugar, which means mixing until pale yellow. Add melted butter, flour and baking powder. Mix. Leave dought to rest for 2 hours.
Preheat oven to 220°C (420°F).
Generously butter your madeleine molds. Spread a bit of flour on top of your molds and turn up side down your molds to remove extra flour.
Fill your molds with madeleine paste. Bake for 8 minutes.
You will get approximately 16 madeleines. Leave your molds to cool in between two batches.