Slice the aubergine thinly lengthways and toss with the salt. Leave to drain in a colander for 30 minutes. Pat dry with kitchen paper.
Heat a large frying pan and toast the coriander seeds. Crush lightly in a pestle and mortar. Heat half the oil in the pan and fry the aubergines in batches until soft and golden. Remove to kitchen paper to drain.
Add the remaining oil to the pan and fry the peppers until meltingly soft. Once cooked, add the aubergines back into the pan and toss with the capers and coriander seeds. Season and serve while still warm.