Just saw this beauty on the Fly Tying Forums.
I love caddis pupa/soft hackles - the lime/chartuese green bodies are so easy to tie - and better off they really do mimic the natural. If you have ever gotten one of those little cone shucks on your hook when fishing and you think it is a stick - take it and squeeze it from the bottom up and see what oozes out. It will have a black head and a lime green body - exactly like this fly.
I would tie this slightly different - I would use the micro-tubing instead of vrib to add less bulk and make the gap between hook and body slightly larger.
Even better! Brett just sent me a link to his site with tying instructions on another pattern. Check out The Trout Addictions Fishable Flies Blog.