Bring broth to a very slow simmer on a burner close to where you'll be cooking the risotto. It's important for your stock to stay hot through the whole cooking process.

In a deep, large pan or pot heat oil. Add diced onion and saute over medium heat until soft and translucent. Do not brown onion. Add the Arborio rice and while stirring constantly "cook" rice for 1-2 minutes until it begins to become translucent on the edges and is well coated in the oil. If necessary, you can add a bit more oil to the pan if it seems too dry.

Add the juice and zest from the two oranges, stirring constantly. When most of the liquid has simmered off, add a ladle full of the hot stock. Stir the rice until the liquid is gone and then add another scoop of stock. The method of adding a small amount of stock, stirring and letting the rice absorb the stock before adding more is the essential steps that makes risotto what it is. Any other method of cooking the rice would essential leave you with a steamed end product and nothing close to the creamy consistency a true risotto will have. Be sure to scrape the bottom of the pan so the rice doesn't stick and always keep the pan hot. On my stove, medium heat is great. It keeps the risotto at a simmer, but isn't so hot that it burns.

Continue to add a ladle full of the stock at a time. After about 20 minutes, your rice should begin to soften, but still be hard enough that it needs a bit more cooking. Give the rice a quick taste test and add salt if needed. There should be no more than about 5 - 10 minutes left before the rice will be done. Add your chunks of fish and another ladle full of stock. Gently stir the fish into the risotto, while still scraping the bottom of the pan to keep rice from sticking. Be gentle with the fish! You aren't trying to break it apart, but lightly cook it in the steam and heat of the rice. Because fish can be rather fragile, it will break apart some, that's fine, you just don't need to encourage it to do so. Continue to add the rest of the stock one ladle full at a time (if you run our of stock you can use hot water instead).

When the rice is about 1-2 minutes from being done, it should be creamy and still very slightly al dente, add butter and parmigiano-reggiano cheese. Stir gently until butter has melted and the cheese is fully incorporated.

Remove from heat and taste. Add more salt if necessary. Serve immediately on a platter or more family style and the way we most often do it, directly from the pan. I like to add a couple of fresh orange slices to the plate and sprinkle a little more orange zest on top too!