This recipe is pretty wordy, and makes this process seem difficult but that’s not the case. Once you do it, it’s very easy. To make plain butter, skip the culturing step and the rest is pretty much the same. The churning process will take a bit longer with uncultured cream.
Cultured Butter
4 cups (1ltr) heavy or double cream
1/3 cup (80ml) plain whole-milk yogurt, crème fraîche or buttermilk (check the ingredients to make sure these do not conatin any gums or stabilizers)
1 1/2 tsp kosher salt (or to taste)
Begin by culturing your cream (this is an overnight process, so plan accordingly). In a clean glass or ceramic container (bowl, jar, etc) combine the cream and yogurt, crème fraîche or buttermilk. Cover loosely and place it in a warmish part of the house - the ideal temperature is around 75F (23C), but anywhere in the range from 70-80F (20-26C) is okay.
After 12-18 hours, the cream should be noticeably thicker and should taste slightly tangy, i.e. like crème fraîche. If it’s bubbling and gassy, some unwanted bacteria have gotten in there so discard your cream and start again (note that this has never happened to me). If it hasn’t thickened yet, leave it alone for another few hours and eventually it will. When your cream has thickened, if you are not ready to make your butter right away, transfer the container to the fridge where you can leave it for up to another 24 hours.
In order to churn properly, the cream needs to be at about 60F (15C). If you’re taking it out of the fridge just let it warm up until it reaches this temperature; if you’re making it from room temperature you’ll need to place the bowl in a bath of cool water for a few minutes to cool it down.
You can use any method you want to beat the cream; handheld electric beater, stand mixer, etc - even whisking by hand if you’re trying to pre-emptively burn off a few calories. If using a kitchen Aid stand mixer, put the cream into the mixing bowl. Cover as much of the bowl as you can with plastic wrap to keep from getting buttermilk all over yourself. You’ll want to equip the whisk attachment. Turn the mixer to a speed of about 6 or 7 and watch the cream carefully. The cream will start to change to a yellow color and consistency will change. You’ll know when the butterfat has separated from the buttermilk when you start to see a lot of buttermilk spattering on the plastic wrap and globules of yellow butterfat will be swimming in a sea of buttermilk. Stop beating and carefully tilt the bowl over a cup, holding back the butter clumps as best you can, and drain away as much buttermilk as possible. You can use this just like commercial buttermilk.
Now you have to wash the butter to get rid of all the residual buttermilk, which would cause it to spoil prematurely. Using a fork, your hands(my preferred implement) or a stiff rubber spatula, pour some of your reserved icewater over the butter, kneading and stirring it around vigorously. The water will turn whitish and the butter will firm up, making it cohere and knead more easily. Pour out the liquid and repeat as many times as needed until the water sloshing around in your bowl is completely clear. After you’ve poured off the last of the liquid, continue kneading for a few more minutes to get as much water as possible out of the butter. If you want salted butter, add your favorite salt now, to taste.
I recommend using a Butter Bell to store your butter. Here’s a link….http://www.butterbell.com