I posted this one elsewhere, but since it has Chartreuse, I'll throw it in again:
3/4 Yellow Chartreuse
3/4 lemon juice
1 egg yolk
S, S, SU
This was an experiment to see how egg yolk works in a cocktail. The Yellow Chartreuse was that last thing I thought to put in (after several iterations). It adds a great amount of complexity to an otherwise straight-forward flavor profile.
I have all of that at home. Except my Chartreuse is green one, not yellow. Do you think it would work OK with the green? (the egg yolk is an interesting twist. I know that whites in sours is "common")