Meaning to clear or purify, this term is used to refer to the process of removing the impurities from fat - usually butter. Clarified butter is widely used in Indian cookery (known as ghee) where it was originally made to extend the keeping qualities of butter, it is also suitable for frying at a higher temperature than unclarified butter or for making cakes.
To clarify butter, gently melt 450g unsalted butter in a small, heavy pan. Simmer very gently until the white milky residue turns golden. This may take from 10-30 minutes depending on the amount of water in the butter. Strain the butter through several layers of muslin, cool and pour into a clean jar.
Traditionally ghee was not stored in the fridge, it can be stored in a covered, clean jar once made for 1-2 weeks or in the fridge for up to 2 months.