From version 1.17 you can fill cauldron with Water,Lava and Powder Snow. So i have a suggestion to add new variable to recipes - Liquid with which you could make potions only in cauldron filled with liquid that you choose.
For example you can only make Fire Whiskey in Lava and Tequilla in Water.
It would also be useful for Lager and Ale because Lager is brewed at lower temperatures. For brewing Lager beer you would use powder snow when for Ale beer you would use water.
RPG servers could use that function too for making potions (like Fire resistance could be made only in lava when normal Resistance would be made only in water).

Sorry for my english. I'm not from English-speaking country.

hi, since this project appears to be dead (re no response on #500), i've added this feature to my fork (BlueMoonVineyard/BreweryNG@fb3a748).