The only one where I recall Ranma evolving the Neko-ken to have a tiger and dragon form is the "Break Her Chains" series by The Grum. However, while Ranma does meet Ukyo, I don't recall any mention of a restaurant and him being a waitress.
Ukyo shows up in book 2. The series is very incomplete, and since I've been waiting over 15 years for it to be completed, I wouldn't hold my breath. No updates to book 2 in that long, although the sequel "Neko Senshi" was updated relatively (for Grum) recently.
http://thegrum.s3-website-us-east-1.ama ... aster.html Still a very good read, and the first book is complete. Also given up hope of "Finding an Anchor" being finished, and while it is labeled "lemon", I only recall lime. Maybe there was supposed to be lemon eventually, but not in what is posted (over 300K on my disk). There IS lime however.