How to make
Arrange the biscuits onto a plastic bag after dipping them in milk first. Arrange them in a rectangle - use 7 biscuits for the length, 3 for the width and make 4 layers for the roll.
Smear each layer with a cream, made from the butter, egg white, powdered sugar and vanilla, all beaten to foam. Put fruit jam and walnuts in the middle.
Then bring 2 of the opposite ends together to form a triangle. Once it's ready, smear it with cream and sprinkle with walnuts.