This farm produces drops from 12 cows in 20 minutes, and it kills the right amount of cows to maintain 25 cows in the farm.
This farm is 3x3x3.5 blocks big, pretty small if you ask me.
An average person (me) can build this farm in 20 minutes from a new world
Only if you use mooshrooms and if you have spare bowls
When there are 25 cows in the farm, breeding the will cause 12 cows to be killed via entity cramming
You don't, to make the farm produce more, make more copies of the farm