Boil slowly the concentrated milk, whisking often till it will be slightly caramelized.

The biscuits: whisk the flour, the baking powder, the soft butter, the sugar, the eggs and three tablespoons of milk.

Whisk quickly the batter and form a ball that will be kept in the fridge for a half of an hour.

Roll the batter and cut round biscuits of 1/2 cm height.

Bake in oven for a quarter of an hour at 170°.

When cold cover abundantly of icing sugar many times a day so that the biscuit humidity will create a sort of compact icing.

Who likes chocolate, can melt a bar of dark chocolate with a small quantity of milk and when still warm brush the biscuits on both sides.