Sterilise a glass jar by running through the dishwasher on a hot cycle and allowing to cool to room temperature or wash with very hot, boiling water, rinsing well before placing in a low oven until it has dried. Again, allow to cool to room temp before using.

Stir the cream and buttermilk together then cover the jar with coffee filter paper or fold up some muslin 2-3 times and fasten around the jar with strong. You want the cream to breathe so don’t use foil or cling film.

Leave to stand for 24 hours. That’s it! If you have a very hot kitchen, it may be ready in less time so take a peek and see if it has thickened by wiggling the jar. When it has soured and thickened, refrigerate and use within 7 days. How easy was that?!