Chop the onion and fry it till it gets into a golden color

Add the salt, black pepper and the nutmeg to the frying onion. Don't use too much or you'll ruin the taste balance of the recipe. A pinch of each one should be enough.

Add slowly the cream into the mix to keep it frying and start removing with energy so the crean mixes homogeneously. Keep removing till the crean gets a brownish color.

Serve the carbonara sauce on top of the spaghetti.