Place the grapefruit juice, grated ginger and honey in a small saucepan. Bring the mixture to boiling point, remove from the heat and leave, covered, to infuse.
Bring the water to the boil in a large saucepan. Add salt then the rice, stir, cover and lower the heat. Cook for around 12 minutes. The rice should be cooked but still retain some bite.
Heat some water in the lower pan of a steamer. Place the fillets of sole in the top compartment and cook for around 8 minutes.
Whisk the grapefruit, ginger and honey sauce then pour it lightly over the fillets of sole. Season then serve immediately with the rice. Ideally, serve the fish hot and the sauce cold.