Heat oven to 190C/fan 170C/gas 5.
Tip the rice into a sieve, rinse under
cold running water, then leave to drain.
Heat the oil in a flameproof casserole,
add the onion, then fry until softened,
about 5 mins. Stir in the rosemary and
mushrooms, then fry briefly. Add the
rice, stir to coat in the oil, then add
the peppers, tomatoes, stock and
some freshly ground pepper. Bring
to the boil, give it a stir, cover tightly
with a lid, then bake for 20-25 mins
until the rice is tender. Scatter over
the parsley and serve.