1 l cream 38 pct. fat
1 dl buttermilk or creme fraiche
6 g salt
The easy way – and one that has often worked for me – is to mix milk and buttermilk, leave it at room temperature for 24 hours and then start whisking. But I prefer and recommend the following method.
Heat cream to 21 degrees celsius. Add buttermilk/creme fraiche. Cover and leave at 21 degrees celsius for approximately 8-10 hours, shaking the container every now and then if you can. When the cream tastes mildly sour, move the container to a room with a temperature of 17-18 degrees celsius for 3-8 hours until it thickens like crème fraîche and starts to smell fresh and aromatic. Stir, move the container to the refrigerator, then wait for the temperature to drop to 8 degrees celsius.
Then comes the churning. Use a large container, as the cream will splash when you start whipping at high speed. The crème fraîche will soon look like whipped cream, and shortly after, it will start to separate: this is when you lower the speed. If you have a stand mixer with a flat beater, you can replace the whisk with this and finish the churning at a low speed until the butter starts to form lumps.
Run it through a sieve to collect the buttermilk, and then change the flat beater for a dough hook. Work the butter a little more until no more buttermilk appears and the butter does not ‘shine’, which is a sign of moisture. Gently mix in the salt. If you like the feeling of coarse salt in your butter, use Maldon or another flake salt and adjust the suggested amount to your liking. Finally, put the butter in the middle of a sheet of parchment paper and roll it up into a tight ‘sausage’. You can also freeze some of the butter, but then it is better to use a plastic container than to use parchment.
