Prepare the broth in a saucepan and bring it to a light simmer. Keep it warm throughout the cooking process, as it will need to be gradually added to the lemon salmon risotto.
Heat the extra virgin olive oil in a frying pan over medium heat. Once hot add the salmon fillet, placing it on its skin. The oil should be hot enough that you hear sizzling when adding the fish.
Cook the salmon on its skin for 3-4 minutes, then cover the pan with a lid and reduce the heat to low. Do not turn or shake the salmon, simply leave it in the pan on its skin.
Continue cooking the fish until thoroughly done. Do not overcook it, as it will become dry. This step will take approximately 10-12 minutes.
Remove the salmon from the pan and separate the meaty part from the skin. The skin should be very easy, as the skin should be very crisp. Break the salmon into bite-sized chunks, and leave it in the separate plate.
The frying pan will have the oil and some fish broth in it. Add some more oil if required, although it shouldn't be the case. Heat it up again on low-medium heat.
Add the finely chopped onion and a pinch of salt to the frying pan. Sautee until the onion is soft and translucent.
Increase the heat to high and add the risotto rice to the pan. Mix well, and toast the rice until it starts to change color, ensuring each grain is coated in oil. (Approximately 1-2 minutes)
OPTIONAL: Add ¼ cup of dry white wine, like Sauvignon Blanc or Pinot Grigio, and stir well, keeping the heat high until all the wine has evaporated. Once done, quickly move on to the next step.
Reduce the heat to low, and add a ladle of broth to the risotto. Maintain a gentle simmer, and continue adding broth as soon as it is nearly all absorbed, stirring frequently (every minute or two).
Keep on adding the vegetable stock and stirring until the risotto rice is cooked. This will take approximately 18-20 minutes.
When you add the last ladle of stock to the risotto, add the lemon zest too. Mix well, allowing the oils from the zest to be extracted.
Once cooked, remove the lemon salmon risotto from the heat. Add the cold butter and grated Parmesan cheese to it. Mix well until the ingredients are well incorporated into the rice.
Taste the rice for seasoning and, if desired, add some freshly ground black pepper to it.
Allow the lemon risotto to rest for a couple of minutes, then add the salmon pieces and serve with a sprinkle of fresh parsley on top.
You can also add a little more zest on top for presentation. Enjoy!