Bring the stock to a boil in a 15cm or 6" saucepan. Taste the stock and add salt if required; your stock should be really quite salty as it is needed to season both the rice and the salmon.
Add the salmon to the stock and poach it for 7 minutes, then remove and set aside.
Dice the shallot and garlic clove as finely as you can.
Heat a 28cm or 11" frying pan or skillet over a medium-high heat and add the butter. When it begins to foam, add the shallot, garlic, and fennel seeds and soften for 2 minutes, stirring occasionally.
Pour in the risotto rice and toast it in the butter for 2 more minutes, stirring regularly.
Pour over the white wine and stir until almost all of the wine has disappeared.
Reduce the heat to medium and add the stock we cooked the fish in a little at a time, stirring regularly, adding more once the pan is once again almost completely dry.Begin with around 75ml (⅓ cup) of stock, and as the rice cooks, you can add more stock at a time.Keep going until the rice is almost cooked and the risotto is creamy. *See note*
Whilst you are cooking the risotto, place the peas in a sieve and run them under cold water to defrost them.
Remove the skin from the salmon and then break it up with your hands into large flakes.
Zest the lemon.
When your risotto is very nearly cooked, stir the peas and lemon zest through the risotto and then add the flakes of salmon to the top. Add a lid and allow to rest for 3 minutes.
Gently stir through the salmon, have a taste, and squeeze in some lemon juice to taste.
Notes
Many people like the risottos a different consistency, I like mine to "flow". That means it should stay separate when you drag through a wooden spoon but it should start to flow back slowly to fill the channel before resting.