I don't know but there is a columnists for the San ANtonio Express News that you can email/write for restaurant recipes, and every wednesday she publishs the recipe you asked for.
I have emailed her a couple times and she got what I wanted. Most notably how to make the chicken and cheese chile rellenos from Chuy's, but unfortunately Chuy's wouldn't give the recipe for any of their sauces.
here is a link to the site and you can search all the old recipes, or email her and ask.
http://www.mysanantonio.com/salife/food/storyindex.htmljim