Deseed the chilis. This enables you to get more chill flavour without excessive heat.
Dry roast the coriander and cumin seeds over low heat. Don't let them burn!
Fine grind the coriander seeds, cumin seeds and black peppercorns. If you are using dried chilis, grind them as well.
Put all the ingredients in a foot processor and create a smooth paste. A Hand blender will do an equally good job.
Once you have made the paste freeze it in an ice cube tray, then store the cubes in a bag until needed