It is a butter obtained directly by beating a whipping cream. It will abound and then will gradually part with butter on one side and on the other, whey.
Unsalted Gourmet Butter
Unsalted Tartine et Cuisine
Pour the liquid full-fat cream into the bowl.
Whip the cream to form a “chantilly”.
Go on whipping for more than three minutes, until the Chantilly begins to granulate and separate out. The butter grains will stick together and a whitish liquid (the buttermilk or whey) will appear.
Continue beating until the butter grains form into a ball. Remove the butter ball, wash it thoroughly to get rid of the whey, then knead it to obtain an even texture.
If you prefer salted butter, add 2% salt.
Mould the butter by pressing it into a small hollow container and keep in the refrigerator.