Place the egg and water in a medium-sized bowl. Take a whisk and whisk them together until they are completely incorporated.
Make sure that there aren't any yolk streaks running through the wash as this will transfer into a streak on top of your baking! You have to really make sure that the two are completely mixed together!
Use a pastry brush to brush an even layer on top of your pastry or baked good. Again, making sure that the layer is even will result in even browning.
Bake the baked good according to the recipe instructions you are using.
Notes
The secret is making sure this is well combined for a streak-free, perfectly browned baked finish!
Egg wash is perfect for when you want to adhere sanding sugar to the top of pie crusts and pastries as well. Simply brush over top then sprinkle the sugar on top and bake as directed.