Open the Crescent roll and flatten the sheet onto a piece of floured parchment on a cookie sheet. Spread warmed Nutella over dough to within a half inch or so of the edges.
Roll from the long edge into a tube.
Place pastry in the refrigerator for about 15 minutes so that it is easier to manipulate.
I skipped refrigerating it once, and it was a mess.
Remove from refrigerator and, using a sharp knife, slice down the center.
Braid the two sides, alternating and twisting slightly so that some of the layers show. Pinch the ends together.
It makes the pastry look amazing! Beat the egg white, and brush onto the twist.
Bake at 350° for about 20-25 minutes. Remove when nicely browned.
Sprinkle with powdered sugar.
Allow to cool slightly. Slice and serve.