For the marinade, mix honey, vinegar, Worcester sauce and 1 tablespoon of oil. Cut fillets from the bone, rinse and pat dry. Cut each fillet into 3-4 pieces and turn in the marinade. Cover and chill for about 1 hour.
Preheat oven (electric cooker: 200°C/circulating air: 175°C/gas: level 3). For the tzatziki, wash the cucumber, cut in half lengthwise, remove the seeds and grate finely. Peel ginger and grate finely. Mix yoghurt, cucumber and ginger.
Season with salt and pepper.
Remove the meat from the marinade and place on a baking tray with the skin facing upwards. Brush with marinade and season with salt and pepper. Bake in a hot oven for 25-30 minutes.
In the meantime, clean and wash the spring onions and cut them diagonally into longer pieces. Heat 1 tablespoon of oil in a saucepan. Brown the spring onions in it. Add the couscous, 1 tsp salt, cardamom and cayenne pepper, stir-fry briefly.
Add 1/4 l water, bring to the boil. Remove the pot from the stove and let everything swell for about 5 minutes. Add butter and loosen couscous with a fork. Serve everything.