For the curd strudel, mix all ingredients into a smooth dough 2. Chill dough for approx. 1 hour. For the curd filling, separate eggs and beat egg whites until stiff.
Cream butter, yolks, sugar, vanilla pudding powder, vanilla sugar, curd, lemon juice, lemon zest. Carefully fold in the snow. Roll out the strudel dough thinly, spread the mixture on the strudel dough and roll it up.
Brush with milk or butter and bake the strudel at 180 °C top/bottom heat.