Heat the olive oil in a saucepan over a medium heat, add your echalion, garlic and chillies and cook down for around 5 minutes.
Add the remaining ingredients. Bubble briskly for 6-8 minutes, until reduced to a thick consistency.
Either use a stick blender or pour into a blender and blitz until smooth. Serve straight away or keep in a sterilised Kilner jar in the fridge for up to 2 weeks.