Place the yeast, sugar and water in a small bowl and let stand for five minutes, or until proofed.

In the large bowl of an electric mixer, cream the margarine and yolks until light, then add the yeast mixture and flour. Blend well. Cover well and refrigerate for four hours or overnight.

In the bowl of an electric mixer fitted with a beater, beat egg whites and slowly add sugar until soft peaks form. Add cornstarch, vanilla sugar and confectioner’s sugar and mix well to combine.

Preheat oven to 350 degrees Fahrenheit.

Divide dough into six even parts. Roll out one part thinly (about 1/8- inch) on a floured surface into a rectangle. Spread filling over dough and roll up jelly-roll style, starting with the shorter end.

Cut into slices and lay each cookie down on its side on a cookie sheet lined with Gefen Parchment Paper. Repeat with remaining dough and filling. Bake 15 to 20 minutes or until just beginning to brown.