Preheat oven to 180°C/160°C fan/gas mark 4. Make 3 diagonal slashes on both sides of each fish; place in a shallow ovenproof dish. Mix together lemon zest and lemon juice, olive oil, parsley and black pepper. Pour evenly over fish; scatter with pine nuts. Cover dish loosely with foil (making sure it does not touch food). Bake in oven for 20-30 minutes or until fish is cooked, and the flesh is opaque and just starts to flake when prodded with a fork. Cooking time with depend on the size of your fish. Garnish with an extra sprinkling of chopped parsley, if you like. Serve with cooked couscous flavoured with chopped fresh herbs (or cooked new potatoes tossed in chopped parsley) and green beans or mangetout. Cook's tips Fresh mackerel can be substituted for the trout. Try using flaked almonds instead of the pine nuts. Lightly toast pine nuts before scattering them over the fish, if you like.