Sauté
the onions in the oil in a large frying pan over
medium heat until softened.
Stir in the rice. Cook for 2 minutes, stirring
constantly.
Stir in the grapefruit juice and when this has been
absorbed, begin stirring in the stock, 1/2 cup (125
ml) at a time.
After about 10 minutes,
add
the butter. Add more stock and cook and stir until
each addition has been absorbed, until the rice is
tender, about 15-18
minutes. Season with salt and pepper.
Stir in the Parmesan and garnish with the parsley.