For the risotto, heat the oil in a frying pan. Add the onion and sweat for five minutes. Add the garlic and rice and lightly sauté for a further 1-2 minutes until the rice is translucent.
Add the water, stock cube and wine and stir over a medium heat for 15-20 minutes until the rice is just cooked and al dente.
Season with salt and freshly ground black pepper, then stir in the butter and half of the parmesan. Spoon onto a plate and sprinkle with the remaining cheese.
For the sea bream, heat a little oil in a frying pan. Pan-fry the fish skin-side down for 4-6 minutes, turning over halfway, until cooked through. Remove the fish from the heat and place on top of the risotto.
For the rocket pesto, place the rocket, pine nuts, garlic, parmesan and oil into a food processor and blend to a smooth paste. Drizzle over the fish and serve.