This is an embarisingly simple recipe. But as I was cooking I kept adding ingredients that seemed somehow right.
So: just stew some cleaned and sliced leeks in olive oil. Add pressed garlic and thyme, if you have it. Stir in crème fraîche at the end with some chopped Camembert, and grate nutmeg over it. Freshly shelled walnuts would have been great, but I remembered too late.
Stir in cooked spaghetti and you have a delicious, simple meal!