Working cookbook for dashing
https://github.com/benbria/dashing-chef
First you need to install RVM. This installs sitewide as root, which really is a bad idea unless no one else uses this machine.
sudo apt-get update; apt-get install curl -y
command curl -sSL https://rvm.io/mpapis.asc | gpg --import -
\curl -sSL https://get.rvm.io | sudo bash