Add a pinch of salt to a large pot of water and bring to the boil. Add the linguine and simmer for 11 minutes, stirring occasionally to avoid clumping together. Test the pasta after 9 minutes – if there’s still a bit of a bite, add the peas and cook for 2-3 minutes until the pasta and peas are both cooked. Drain, reserving 3-4 tablespoons of the pasta water in a jug, then return the pasta and peas to the pot and reduce the heat to the lowest setting.
Add the flaked trout to the pasta and peas along with the crème fraîche and herbs and stir well. If the sauce is too thick, use some of the reserved cooking water to thin it out to your preferred consistency. Season with some freshly ground pepper and serve in warm bowls – this does cool very quickly.