2) While fish is cooking, char grill the courgettes. First heat a char-grill pan, then brush the courgette slices with the remaining olive oil. Cook them in batches until lightly browned, turning once.
3) Finely grate zest from the lemon, then thinly slice half the lemon and squeeze the juice from the remaining half.
4) Add courgette slices to the fish with the lemon zest, lemon slices, lemon juice and capers. Season with salt and pepper and heat for a few moments. Serve.
Cook's tip: mashed potatoes beaten with mashed butternut squash make a tasty accompaniment to the fish.