I made butter today. Took half an hour including cleanup. Detailed instructions are found at Cooking for Engineers.
I started with 2 quarts of heavy cream and 2/3 cup of cultured buttermilk. The cream and buttermilk mixture fermented for about 12 hours. Into the KitchenAid with the whisk attachment, rinse off butter, and viola!
Yielded 777g of butter and a bunch of buttermilk. I will use the buttermilk to marinate chicken for fried chicken tomorrow. It costs about $6 per pound for butter this way. I am going to see if I can find a raw milk supplier and skip the whole heavy cream purchase next time.
Fresh butter on homemade sourdough bread, 'nuff said.