Same weight of eggs, sugar, butter, flour and chocolate with milk
Make an ointment butter (it must have the consistency of a thick cream) and add the sugar. Smooth, being careful that the mixture remains creamy all the time of the preparation.
Add the eggs one by one with a little flour at the same time to keep the creamy consistency of the device
Melt the chocolate in the microwave (or in a bain-marie as you prefer). Add it to the device without working: it's a mix. Do not stir the preparation too much, otherwise cooking will be worse.
Bake in preheated oven at 160 ° C. There is no cooking time because it depends on the weighing. Plant the blade of a knife in your cake: it is cooked when the blade comes out dry.