More Waffles

Supposedly these stay crisp. I found it on some blog which I can't recall, otherwise I would provide a link or citation. Sorry.
Sift together:

* 1 1/2 c flour
* 3 t baking powder
* 2 t sugar
* 1/2 t salt

Gradually stir in:
* 1 c milk

Stir in:
* 2 egg yolks (well beaten)
* 4 T melted butter

Gently fold in:
* 2 egg whites (beaten)