To prepare the batter whisk the eggs and sugar until obtaining a white paste. Gradually add the sifted flour and baking powder; then add the butter and milk.
Add the coffee aroma or liqueur; mix thoroughly. Then refrigerate for at least 30 minutes.
Preheat the oven to 220°C . Spoon the batter into the molds. Bake 3 to 4 minutes, then lower the oven temperature to 180°C and keep baking 3 to 6 minutes or until the edges of the madeleines are golden brown.