1.Preheat oven to moderately slow, 160°C. Line an oven tray with baking paper.
2.Place tomatoes on tray and drizzle with oil. Season to taste. Bake, 10-15 minutes, until tender.
3.Meanwhile, cook fettuccine in a large saucepan of boiling, salted water, following packet instructions. Drain and return to pan.
4.Heat remaining oil in a frying pan on medium. Sauté fennel, onion and lemon zest, 3-4 minutes, until tender. Add prawns and capers, frying, 2-3 minutes, until prawns are almost cooked through.
5.Stir cream and tomatoes through. Simmer, 1-2 minutes.
6.Toss sauce through pasta with dill. Season to taste. Serve with crusty bread.