Preheat the oven to 300°F (150°C) mark 2.

Bring a large saucepan of salted water to the boil, add the rice and boil briskly for 4 minutes, then drain.

Peel and thinly slice the onions.

Melt 2 oz (60 g) of the butter in a large, fireproof casserole dish; add the onions and stir well to coat with the butter.

Add the rice, 1/2 tsp salt, a little freshly ground white pepper and stir well.

Cover tightly and cook in the oven for 1 hour, stirring now and then. The onions and rice should be tender and very pale golden brown when done.

Add a little more salt and pepper if necessary, followed by the cream, cheese and the parsley.