How to remove chromebrew - chromebrew/chromebrew GitHub Wiki

You can simply run:

rm -rf /usr/local/* 2> /dev/null
"$(which sed)" '/source.*profile/d; /# DO NOT DELETE THIS LINE/d; /# See .*profile for further details/d' ~/.bashrc > ~/.bashrc

If you have Crouton installed and you want to restore your chroots, run this command afterwards:

sudo mkdir -p /usr/local/bin/
sudo ln -s /mnt/stateful_partition/crouton/chroots /usr/local/
sudo curl -L https://goo.gl/fd3zc -o /usr/local/bin/crouton
sudo chmod +x /usr/local/bin/crouton
for chroot in "$(ls /mnt/stateful_partition/crouton/chroots/)"; do sudo crouton -n "${chroot}" -u; done

Another way to do it, although more nuclear, is to Powerwash.

Always be sure to create a backup before using any of these methods.