Trim off the ends of your green beans, then plunge them into a big pot of well-salted boiling water. Cook them until they are quite al dente, remembering that they will cook some more later. This should take no more than 5 minutes or so, depending on the size and quality of the beans.

While the green beans are boiling away, gently sweat your chopped shallot in the butter in an ample skillet or sauté pan until soft but not browned.

Transfer the green beans from the boiling water right into the skillet and mix them well with the butter and shallot soffritto. [NB: If you like, you can 'refresh' the green beans in cold water before adding them to the skillet, which will help them retain their color, but being a bit lazy I often skip this step.] Raise the flame just a bit and let the green beans braise for a few minutes, stirring frequently, so they can absorb the flavors of the soffritto.

Now add your cream, enough to just about cover the beans. Season with salt, pepper and nice scrape of nutmeg. Raise the flame a bit more so that the cream bubbles fairly vigorously. Continue stirring from time to time, and simmer until the cream has thickened into a saucy consistency. Taste and adjust for seasoning if need be.