Vanilla-Infused Tomato Sauce

Serves 4.

In this variation on Marcella Hazan’s famous sauce, vanilla’s sweet aromatics make a charming complement to tomatoes, taming their acidity with a little help from good old butter. Allspice and bay add another flavor layer and bridge the sweet-savory gap. This sauce is terrific with roast cauliflower, ricotta gnocchi, lobster ravioli, and grilled or pan-fried fish, such as monkfish or haddock.

1 medium onion, peeled and cut in half
5 tablespoons butter
3 allspice berries, lightly cracked
1 bay leaf
1 vanilla bean
½  teaspoon sea salt
Black pepper, to taste
1 can (28 ounces) plum tomatoes with juices

Put the onion (cut side down) and the remaining ingredients into a sauce pan. Use your hands to break the tomatoes into rough pieces, removing any tough, stem-end bits. Add ½ cup water to the pan.

Set the pan over medium-high heat and bring its contents to a boil, then turn the heat down to medium-low. Simmer the sauce, stirring occasionally, for about 45 minutes, until the fat is floating on top, around the edges.

Pick out the onion, vanilla bean, and spices.* Stir the sauce — it should be glossy. If it’s not, stir in another tablespoon of butter. Taste and add salt or pepper if needed. You can crush the tomatoes further with a spoon or purée the sauce with a immersion blender.

Wash and dry the vanilla bean and save it to use another time. The sauce will keep nicely in the fridge, for a couple of days.

•  For a cook’s treat, cut up the onion and top it with toasted bread crumbs, a little Parmesan cheese, and some black pepper.