What is your favourite mob farm to do in minecraft

for me is the enderman farm in 1.14 that is the best option to win xp

Iron golem farm works well try it :D
You can make it in survival with villagers just look iy up on youtube

i also like the endermen farm in 1.14.
in the older versions, it'd be the pigmen farm. tons of xp and free gold

I've spent a lot of time making massive gold farms. Endermen farms are really fun and satasfying but to me there's just nothing like hitting 1 pigman and having them all drop down and gaining a boatload of exp. seriously gold farms are some of the most enjoyable farms IMO despite the lag.

Villager farm because i love the sound of doors opening and closing constantly.

I like to make very basic cave spider grinders for anything to due with factions until Iobtainblaze spawners. other then that I really like automatic cow farms.