How to make
Heat the oven to 390°F (200 °C). Butter 4 souffle forms and sprinkle them with sugar.
Beat 1 whole egg with 1 egg white with the flour and cocoa. Bring the milk to a boil in a small pot and add it to the egg mixture, while stirring nonstop.
Return the mixture to the pot and stir on low heat until it thickens. Right before it comes to a boil, remove from the stove and leave it to cool. Once it cools, add the left over egg yolk.
Beat the 4 egg whites with a pinch of salt. Carefully add the whites to the mixture. Fill the forms and bake the souffles for 20 min. Take them out and sprinkle with powdered sugar.