Sterilise 1 or 2 small glass bottles by washing in very hot soapy water, rinsing well then putting in a 180C/fan 160C/gas 4 oven until completely dry.

Put the oil and chillies in a small pan and gently heat until you see tiny bubbles. Turn off the heat and leave to cool completely. Strain the oil into bottles and add in a few of the chillies, if you like.