Put the couscous in a heatproof bowl. Add the hot water. Pop a lid on top or cover it with clingfilm. Put it on one side.
Trim and rinse the leek(s). Slice into thin rings. Halve the peppers. Scoop out the seeds and stem. Roughly chop. Chop the tomatoes. Peel and grate/crush the garlic. Grind the cumin.
Warm a splash of olive oil in a deep frying pan. Add the leek(s) and peppers. Season. Fry. Stir now and then till the veg are lightly coloured.
Add the garlic, cumin and chilli. Stir them round the pan to flavour the oil.
Stir in the tomatoes and chickpeas. Half fill the chickpea tin with water. Add that to the pan (add a whole tin if you’re cooking for four). Pop on the lid.
Let the stew simmer for about 5 mins. Taste. Season. Slide the trout into the pan. Pop the lid back on.
Cook the trout fillets cook in the stew for a few mins till they’re opaque. Rake the couscous with a fork to fluff it up. Serve the trout and chickpea stew with the couscous.