Mix together the egg yolks, the egg, sugar, peanuts, flour and margarine.
Work it with your hands until you have a very smooth doughball.
Leave to rest in the fridge for 1 hour.
Roll the dough out using a rolling pin and cut it to the desired shape.
Brush the biscuits with some lightly beaten egg white and sprinkle over some sugar.
Put them in an oven tray dusted with flour and bake at 180ºC for 20 minutes.