Preheat your oven to 350°F (175°C).
In a mixing bowl, beat cream cheese, sugar, vanilla, and egg yolk until smooth.
Unroll the crescent rolls and place the sheets on a greased baking sheet.
Spread the cream cheese mixture evenly down the center of each sheet.
Fold the sides over the filling, slightly overlapping, to create a braid effect.
Beat the egg white with water and brush over the top.
Bake for 20-25 minutes until golden brown.
Cool slightly before slicing and serving.