2 tablespoons unsalted butter
1 small onion, finely chopped
Salt and freshly ground pepper
3 3/4 cups chicken broth (or 3 3/4 cups water and 2 chicken bouillon cubes)
1 1/3 cups tubetti (my preference) or elbow macaroni (traditional)
1/2 cup heavy cream
1/2 cup freshly grated Parmesan
3 1/2 tablespoons mascarpone
Melt butter in a large skillet or saucepan over medium-low heat. Toss in onion, season with salt and pepper, and cook, stirring, until soft and translucent, about 10 minutes. (Or, if you’d like, go ahead and cook the onion until it’s golden.) Pour in chicken broth or water and bring to a boil; if you’re using bouillon cubes, drop them in now and stir to dissolve. Add pasta, stir it around, and let it cook at a steady simmer until it has absorbed almost all the broth, 20 to 25 minutes. (There should be just 1/4 inch or less of liquid bubbling at the bottom of the pan.)
Pour in cream and allow it to simmer for about 3 minutes, until it thickens slightly. Stir in Parmesan and mascarpone, cook for 1 minute, and taste for salt and pepper (it should be generously peppered). Pull the pan from the heat, cover, and let rest for 3 minutes before serving.
You can certainly serve this as a side dish to a roast of almost any kind, including chicken—think of it as a fancy macaroni and cheese—but it’s elegant enough to come out on its own as a starter or main dish. It can be eaten plain or with a dusting of parsley or a little more Parmesan; of course, if you have some truffles to grate over each portion, go for it.