Didn't have rabarbaro available so used 1/3 oz averna and 1/4 !rhubarb liqueud instead. Was really tasty! Averna brought up some smoky chocolatey notes and the rhubarb provided tartness.
this sounds delicious as a drink, I'm going to try this because I have some homemade rhubarb liqueur, but also rhubarb and averna are nothing like rabarbaro tastes like :P