Preheat the oven to 200°C, 400°F, Gas 6.
Heat the olive oil in a large saucepan, add the onion and sweat for 8 minutes, without colouring, until soft, stirring every now and then.
While you are waiting for the onion to cook, put the haddock in a small baking tray, pour over the cream and cover with foil. Place in the top of the preheated oven for 10-12 minutes until cooked. Remove and keep warm.
While the haddock is cooking, add the rice to the onions and continue to stir until the rice has turned translucent. Now add the wine and, when reduced, slowly add the hot stock, a little at a time, stirring every now and then. When almost all of the stock has been incorporated or the rice is almost cooked, add the runner beans and cook for a further 2 minutes.
When the rice is cooked, break up the haddock slightly then stir into the rice with the cream. The haddock should break up a little more as you stir. Turn off the heat and add nearly all of the Parmesan and season with salt and cracked black pepper.
Serve in warm bowls with the remaining Parmesan sprinkled over the top.