Slime Farms
Slime Farms are slightly modified on Vanilla+ due the majority of 1.21 Oozing Slime Farms do not work due to Vanilla+'s entity cramming limit being set to 8 entities with scaffolding and vines not preventing entity cramming.
Manual Slime Farms
This Slime grinder uses trial chambers to quickly farm stacks upon stacks of slime in a very short period of time and is all you need if you do not need an excessive amount of slime.
Automatic Slime Farms
This Slime farm utilizes a spawn biome to automatically farm slime and is a great choice if you need a lot of slime.