All you need is:
- a clean jar with a leak-proof lid
 - heavy whipping cream
 
Seriously that's it.
All you do is pour the whipping cream into the jar - I did about 1/2 cup at a time.  Then you close the jar tightly and start shaking it.  I just alternated arms when I got tired, but within 9 minutes, the buttermilk separates from the milk fat (which is butter!).  Simpy pour the buttermilk out of the jar, and you can use that for whatever people use buttermilk for.  Then I put the butter into a covered bowl for the fridge.  If you leave it out on the counter for a few days (like I do), it'll sour.  So refrigerate! :)
Step 1.  Pour the milk into the jar.
Step 2. Shake - shake - shake!
3 Minutes later, we have whipped cream (without the sugar)
 After about 6 minutes, we start to see separation.
After 9 minutes, we have completely separated the buttermilk from the milkfat.
Just pour the buttermilk out (into a bowl or whatever) and then you have butter!
I used the butter immediately to make an egg for breakfast.  It tastes just like the unsalted butter I normally buy, but haven't in a while because the prices have gone up so much.  
Let me know if you try it!





