Heat the olive oil in a frying pan over a medium heat. Add the chorizo and cook for 5 minutes, or until golden.
Add the prawns and cook for 1-2 minutes, or until just pink.
Stir in the rice, tomatoes and spring onions. Leave to cook over a low heat for 10-12 minutes, until a golden crust forms on the bottom of the pan and the tomatoes have softened a little.
Break up the rice with a fork and season to taste. Scatter over the parsley and serve.