Yep apply on top of the dough after 2nd rise and beforw baking. On other types of bread, they dont put egg wash on top before baking but they put it in the middle of the baking, but it might affect the dough so I do t recommend it. They do it on korean sausage bread. If you want a more shiny and perfect top, apply the double egg wash method. Put 1 layer of egg wash on top, wait for few minutes for it to dry out a bit, then apply 2nd coating of egg wash