home made butter
. . . . . . . .
(of the heavy whipping kind).
fill the jar halfway with cream.
screw its lid tightly.
shake, shake, shake, shake. shake.
shake. you need to keep on shaking.
like a lot. this is a workout.
refer here for a good way to shake. you don't want to do it too vigorously, more a jolt or whip back and forth.
even keep shaking when it turns to cream and you feel like you're doing nothing. eventually the fat (butter) will separate from the liquid (buttermilk) and it'll feel like you're shaking something again.
When you do start to see butter forming (after about 7 minutes of shaking) unscrew the lid and pour out the buttermilk.
keep shaking and removing any buttermilk that forms out,
till you can no longer :)