The rough part of making your favorite meals in New World are the limited and hard to find ingredients. Yeast is just ONE hard to find resource!
Currently Yeast can be found in Monarch’s Bluffs, Brightwood, and Shattered Mountain. There’s a catch though: You still have to grind Provision crates which have a chance to spawn your needed ingredient.
Provision crates will respawn around the 45 minute mark after you have opened them.