Depends if you want to make it hotter at the start of the cooking (in which case more chilli powder or finely chopped fresh chillies) ....or at the end (in which case some chilli sauce). You can't add chilli powder at the end, because it needs "cooking in".
thanks all for your answers, yes think chopped chillis which I have a few in the freezer probably would do - next time will try that.
cousin said it was very tasty to her but she was only in from work, tired and hungry, and unexpected it so enjoyed it - but deffo could have been hotter.
I've posted before, get some goat if you can, I always cook two a Korma for Mrs Tony and madras for me. But Lancashire hot pot in slow cooker for tonight, just have to nip and get French stick.