Preheat the oven at 375 F.
Mix the eggs, eggs yolk and sugar until the color gets light and creamy.
Add the flour gradually and mix.
Add salt and baking powder.
Mix red coloring, cocoa powder with melted butter.
Add red mixture to the flour and egg mixture and let it rest 10 minutes in the refrigerator.
If the pan is not non sticky, brush each madeleine hole with butter, sprinkle with flour and shake off excess.
Put approximately 1 teaspoon of batter in each hole.
Bake for 12 minutes and repeat until there is no more batter.