This world quest provides the rank 2 recipe of
if you don't have it.
Rank 1 recipe is from
and Rank 3 is via discovery.
Rank 1 uses 25
Rank 2 uses 20
Rank 3 uses 15
You don't need to craft the potions yourself in order to complete this quest. You just need to have the potions in your inventory (I don't know if you can have them in your bank - but if you have them in your bags you're safe). So you can let another player craft them for you or buy them off the AH, and it will still count as long as you are able to hand in two potions to the questgiver.
Are you here to deliver supplies?
Thank you for assisting us, alchemist. We needed these potions badly.
Legion Alchemy Guide