Cook the spaghetti for two minutes less than the pack instructionsm and reserve the water once done.
Heat the oil in a large frying pan over a medium heat and fry the garlic for 2-3 minutes until softened but not coloured. Stir in the creme fraiche, lemon juice, Parmesan and 2 ladles of pasta cooking water. Simmer gently for 1 minute.
Add the drained spaghetti to the frying pan. Cook for a further 2 minutes, until reduced to a creamy sauce that coats the pasta.
Add the smoked salmon and chives or dill, season with freshly ground black pepper and divide between four bowls or plates.
Garnish with lemon zest and top with a handful of rocket.