Heat the oil in a large frying pan and cook the onions, carrots, courgettes and pork for 5-10 minutes, until browned.
Add the chillies (optional), mixed herbs and garlic cloves and cook for 30 seconds before adding in the tomatoes, 1 litre of stock and the rice.
Bring to a simmer, and cook for 15 minutes, stirring occasionally, until the liquid has been absorbed. Add the remaining stock and cook for a further 10 minutes, until the rice is cooked. Season and serve.