Mix the eggs and the sugar. Mix the flour and the baking powder and add them to the eggs, mix vigorously. 

Melt the butter at 40-45°c, add to the preparation and mix. Add the lemon zest and the sachet of Supercress 5 and mix until the mixture is homogeneous. 

Pipe the madeleine mixture into the moulds. Let stand 10 minutes. Bake at 180°C, 10 to 12 minutes.