Preheat the grill to high. Combine the couscous, apricots and 1 tablespoon of the olive oil in a bowl. Add 260ml very hot water, cover with cling film and let sit until all of the water is absorbed and the couscous is tender, about 5 minutes.
Stir together the yoghurt, hummus, mint and 1 to 2 tablespoons water in another bowl. Season with salt and set aside.
Toss the prawns, tomatoes, the remaining 1 tablespoon olive oil and paprika together. Spread out on a baking sheet and broil until the shrimp is opaque and cooked through, about 4 minutes. Drizzle with the lemon juice.
Fluff the couscous with a fork. Divide the prawns and couscous among 4 plates. Scrape any of the drippings from the baking sheet into the yoghurt-hummus sauce. Serve the prawns and couscous with the sauce.