take it slow and gradually add more wet ingredients to create a nice smooth paste. you want it fluffy and thick, not thin and runny.
if you have a pastry bag, you can pipe the mixture into the halved egg whites. i have a pastry bag, but honestly it's a lot easier to spoon in the mixture and less of a mess at the end. evenly fill all the egg whites. start out small, to make sure your mixture goes all the way and then top them off if your left with yolk mix. you should should be left with enough yolk mix to pile high fluffy eggs like the opening 