The Vegan quirk is a random trait that could potentially be spread by Gurus in the same dome. Considering other achievements in this game, however, I found the easiest solution to be to build up a colony to be self-sustaining (all wonders + copious amounts of drones and shuttles to automate 99% of the work) and then build many, many domes with many, many farms and just leave the game running.
I progressed 40 Sols over about 3 hours and my population went from 2100ish to about 3400ish. With so many factories and production facilities going I never wanted for resources. Drones took care of the rest. When I saved, I popped both this and the Post Human achievement (have a colonist with 2 rare traits):
For simplicity, if you really want to gun for this, select the International Mars Mission and choose a low difficulty landing site. That will equip you with the easiest environment to build up a self-sustaining colony. This achievement in particular is strictly a numbers game, so gun for that massive colony size.