With an electric whisk beat the eggs with the sugar, then add the flour and mix well with a whisk by hand. Melt the chocolate in a bain-marie with butter and add to the mixture of eggs, flour and sugar. Mix and pour into a cake tin.
Cook the cake in a preheated oven at 180ºC for about 25 minutes (it should not dry inside).
Cool it in Freddy® with the function of blast chilling for about twenty minutes, serve it with a dusted with powdered sugar.