Heat the oil in a frying pan. Fry the shallots and garlic until golden, then transfer to a blender.
Fry the shrimp and chillies for 1–2 minutes, then add to the blender with the remaining ingredients. Mix, adding as much of the frying oil as necessary to make a pourable paste.
Put the mixture in a saucepan and bring to the boil. Reduc