Heat the butter in a saucepan, add the onion, celery and garlic and cook over a low heat for 5 minutes or until softened. Add the fennel and cook for a further 30 seconds.
Remove from the heat, then pour over the wine and brandy. Return to the heat and cook over a high heat for a couple of minutes until reduced down, then add the tomatoes and herbs and simmer for 15–20 minutes, adding a little water if needed.
Remove the pan from the heat. Discard the herbs, then using a stick blender, whizz to form a smooth sauce. Stir through the cream and season. Meanwhile, cook the pasta in a large saucepan of salted boiling water according to the pack instructions until al dente.
Heat the oil in a large frying pan, add the prawns and cook for 3 minutes on each side or until pink and cooked through.
Drain the pasta, reserving a little of the cooking water. Toss through the sauce, adding a little cooking water to loosen if needed. Spoon into bowls and top with the prawns. Serve sprinkled with the basil.