In a saucepan, cook the onions in olive oil over medium heat, until they get tender.

Then mix in the saffron and continue stirring for another minute.

Add in the rice and stir until it is well coated with the butter.

Pour the grape juice over the rice mixture, and mix until it evaporates.

Add in 1 cup of broth and stir constantly to prevent the rice from sticking to the bottom and sides of the saucepan. Cook until most of the liquid is absorbed.

Keep on adding broth, one cup at a time and make sure to wait until most of the liquid is absorbed before adding the next one.

Cook for about 15 minutes or until the rice is tender. Add in the Parmesan cheese and the remaining butter and mix well.

Serve hot.