Assemble the rolls: On each crescent roll triangle, add 1 teaspoon of chocolate hazelnut spread, and using an offset spatula, spread it around evenly, leaving a 1/2-3/4-inch margin from the edge.
Make the egg wash: In a small mixing bowl, add 1 egg, 1 tablespoon of water, and 1 teaspoon of pure vanilla extract, then using a small whisk, combine the mixture together.