Cut the butter into small pieces. Mix quickly with flour, cream, egg yolk, vanilla sugar and a pinch of salt to form a dough and refrigerate for an hour.
Beat the egg white until stiff, gradually adding powdered sugar and beating until the mixture is glossy. Fold in the almonds.
Roll out the dough thinly on a well-floured work surface, add a little flour if necessary. Spread the egg white cream on top and divide the dough into 40 rectangles. Carefully lift the pieces with a flat knife onto a baking sheet lined with baking paper and bake in the oven at 180 degrees for about 15 minutes. Let cool down.