Start by cooking the tagliatelle pasta according to package instructions until al dente (tender but firm).
As the water for cooking pasta is coming to a boil and the pasta cooks, prepare your ingredients: chop the salmon into inch sized pieces, wash and finely chop the spinach, finely chop the onion and parsley (if using).
In a medium sized saucepan, melt the butter. Add the chopped spinach and sauté until the spinach wilts. Add the onions or shallots and sauté until soft and translucent. Mix everything together.
Add the flour to the spinach and onion and mix until well incorporated. There should be very little of the white flour visible.
Slowly add the cream into the spinach-onion-flour mixture, stirring all the while. Then add the milk. Bring the sauce to a gentle simmer (do not boil).
Add the chopped salmon, salt, pepper, nutmeg, and lemon juice. Gently stir together and cook for 5 minutes. Turn off the heat and let stand until the pasta is ready or remove from heat and serve.
Drain the pasta and serve with the spinach salmon sauce.
Notes
- The amount of salmon seems kind of small, but it's a good amount for this pasta. You can add more salmon if you want more fish in yours.- The sauce in this pasta is more on the "runny" side. If you want it to be more thick, add 1/4 cup less of cream and milk. You can also add a bit more flour.