500 ml (2 cups) pouring cream
sea salt flakes
finely grated black truffle, to taste

  1. Whisk the cream in an electric mixer until it separates into large yellow clumps of butter and a whey-like liquid. Pour through a sieve set over a bowl, discarding the whey. Rinse the butter under cold water, massaging to remove any traces of buttermilk, as these will cause the butter to turn rancid more quickly. Add salt and truffle to taste and massage to combine.
  2. Place the butter in an airtight container and refrigerate until required. It will keep in the fridge for up to 2 weeks.