Heat the oil in a pan. Sauté the shallots for approx. 3 mins., add the rice and sauté until translucent, stirring constantly. Pour in the wine and reduce completely. Add half of the fennel, set aside the remainder of the fennel. Gradually add the stock, stirring frequently, so that the rice is always just covered with liquid, simmer for approx. 20 mins. until the rice is creamy and al dente.
Heat the oil in a frying pan. Fry the prawns for approx. 1½ mins. on each side, remove, season with salt. Roughly chop half of the prawns and mix into the risotto. Stir fry the garlic and reserved fennel for approx. 3 mins.
Mix the cheese, butter, lemon zest and juice into the risotto, then season. Plate up the risotto, top with the remainder of the prawns and the fennel.