Bring plenty of salted water to the boil. Cook the pasta in it al dente for 8-10 minutes.
In the meantime, peel the onion and chop it very finely. Heat the butter in a saucepan and sweat the onion in it until translucent. Peel the garlic clove and press it through the press. Pour on the white wine and reduce the liquid almost completely. Pour in the cream, bring to the boil and reduce by almost a third in an open saucepan. Season to taste with salt, pepper and lemon juice.
In the meantime, cut the salmon into small cubes. Rinse off the chives, cut into small pieces, stir into the hot sauce with the salmon cubes and let stand for 1 minute.
Drain the pasta, distribute on plates and pour the sauce over the middle.