Place the rice in a saucepan and pour over the boiling water. Bring back to the boil, then reduce the heat to low. Cover and simmer for about 15 minutes, or according to the packet instructions, until the rice is tender and all the water has been absorbed.
Meanwhile, peel the oranges and cut them crossways into slices about 1 cm thick. Stack the slices 3 or 4 at a time and cut into quarters. (If possible, use a chopping board with a well to catch the juices.) Set the orange slices and juice aside.
Heat the oil in a large nonstick frying pan over medium-high heat. Cook the pork medallions, in batches, for 2–3 minutes on each side. Remove the meat with a slotted spoon and set aside.
Reduce the heat to medium then add the onion, capsicum strips, carrot and garlic to the pan. Cover and cook, stirring frequently, for 5–6 minutes or until the vegetables start to soften. Add 2 tablespoons water, then 100ml orange juice and balsamic vinegar. Stir well to mix. Cover and cook for 3–4 minutes or until the vegetables are tender.
Return the pork to the pan. Add the olives, orange slices and their juice and the basil leaves. Cook for 1 minute to reheat the pork, stirring well. Add pepper to taste.
To serve, divide the rice among 4 warmed plates and place the pork medallions and vegetables on top. Drizzle over any juices remaining in the pan and serve immediately.