Start by cutting the salmon in small cubes of 1 -1.5 cm. Place a large and deep saucepan over medium heat pour 1 tablespoon of the oil and add the salmon, cooking for 2 minutes while tossing frequently. Season with the salt and pepper and remove from the pan. Keep aside.
In a large pot bring water to a boil on high heat adding a generous amount of salt. Add the pasta, stirring occasionally so as not to stick and cook according to suggested time on the box of the pasta less 2 minutes. Reserve ½ cup of cooking water.
In the meantime, in the same pan that the salmon was cooked add the remaining oil over medium heat and heat-up for a minute. Toss in the spring onions sautéing until they get soft, 2-3 minutes. Return the salmon to the pan and deglaze with the vodka, while allowing for its alcohol to evaporate.
Strain the pasta, add the fresh cream to the pan with the salmon, stir to incorporate and softly smash the salmon cubes with the back of a spoon/spatula. Return the pasta to the pan over low heat, add the lemon juice and zest, stir for a minute so as the pasta absorbs the sauce and add from the reserved water if consistency is on the thick side.
Serve in a flat dish, sprinkle with the chives, add the Parmesan cheese and serve.