They showed up for me in the "Crafting" tab of the build menu.

but you might have to pick up sone items again to unlock the new recipies though. All the new build/crafting items didn't jsut auto unlock for me after the update. I had to pick up some things again for the build/crafting lists to refresh.

The cauldron upgrades used tin, danilion, thystle, muchrooms, carrots (i think) and I think a turnip. so I'd start with those.

Might be a good idea to go through all your low and mid tier ingrediants and metals and see what else gets unlocked.

hope this helps