Cream sugar and cream cheese together; add vanilla and sour cream.
In a 9x13 inch pan, lay 1 package crescent rolls flat to cover bottom. Mix together cream cheese, vanilla, sugar, and egg yolk. Spread cream cheese mixture on top of first layer of crescent rolls. Lay 2nd package of crescent rolls flat on top of cream mixture. Spread egg white (slightly beaten) on top. Mix sugar cinnamon and nuts. Sprinkle on top. Bake at 350 degrees for 30 minutes.