Heat the olive oil in a heavy-bottomed pan, add the onion and cook, until just softening. Add the garlic and cook for another minute. Add the rice and stir it to get it coated in the juices. Pour in the wine, stirring continually. Now the chicken stock a ladleful at a time, stirring continually. It will take about 25 minutes to stir in all the liquid. About 5 minutes before the end of cooking time, add the prawns to heat through. Season and stir in the zest and lemon juice. Top with wild rocket. Serve with an ice-cold Peroni.