Place a roasting pan into the oven and preheat the oven to 450°F.

For the quick pickled cucumber salad, combine the vinegar, sugar and a pinch of salt in a bowl, stir until the sugar and salt have dissolved. Season with pepper. Add the cucumber and onion. Stir to coat. Cover and set aside.

Spray the cauliflower with oil. Sprinkle 1 tablespoon of Moroccan seasoning over the cauliflower and turn to coat. Place the cauliflower into the hot pan and roast for 10 minutes.

Spray both sides of the fish with the oil and sprinkle with the remaining Moroccan seasoning.

Remove the cauliflower from the oven, turn the cauliflower over and, add the fish to the roasting pan. Roast both together for a further 15 minutes, or until the fish is cooked through.

Drain the pickled cucumber and onion and return to the bowl. Add the tomato and arugula and toss to combine.

Divide the fish and cauliflower between two serving plates. Serve with the salad.