What if you had a dinner date with spaghetti and tomato sauce, and the tomato sauce excused itself to slip into something a little more comfortable? Something a little slinkier, a little silkier, a little more sensual?
Ok, you’d probably run away horrified, and the sad-eyed looks people gave you every time you mention the time your dinner tried to seduce you would eventually drive you insane.
BUT! Let’s say you have a fair tolerance for inanimate objects coming on to you. What do you think would make tomato sauce more seductive? Yes, exactly. Butter. And if you said onion too, well, go out and get a ring, because you’re about to have your breath taken away.
Check it: a tomato sauce that starts out tart, and yet subtly sweeter than normal; not sugary, but a mellow sweetness from whole simmered onion. It goes from there to a warming richness, the creamy taste of butter, and after that, the lingering depth of slow-cooked tomatoes. It’s one of my favorite things on earth to make, because it never fails to blow minds. You’d have to try hard to make a sauce simpler than three ingredients, you’d have to be a magician to make them come together more seamlessly. It’s a sauce that some people describe as being “sweet and summery,” and others “velvety and lush,” and the reason you can have such opposing descriptions is because the flavors are so beautifully balanced.
This is not a recipe I came up with, and it’s not even a recipe I secretly found. Marcella Hazan’s “Tomato Sauce with Onion and Butter” from Essentials of Classic Italian Cooking might be the most-blogged about pasta sauce on earth. I first came across it on my friend Molly’s super-lovely Orangette; she got it from her friend Adam the Amateur Gourmet; the Kitchens both Smitten and Steamy have salivated over it, and many more superstar bloggers have fried pixels over this business.
The original seriously couldn’t be simpler: You put a can of tomatoes in a pot with about half a stick of butter and one onion, halved, and simmer for 45 minutes. Done. Heaven. My version, below, is a half-degree more complicated because I really like the flavor and aroma of onion in butter, so I have you cook those two together for a few minutes first. And, because I love the idea of showing two versions of onion flavor, I serve the pasta with a tiny onion and herb salad that takes one minute to make. It adds an element of crunch, and a sharpness of raw onion to accentuate the smooth, slow-cooked flavor in the sauce. Because nothing is sexier than a little bite.
Buttered Onion Tomato Pasta
Serves 4 as a main course, 6 as a starter
5 tablespoons butter
1 medium onion, peeled, cut in half along the equator
1 28-ounce can tomatoes with juice (there are hardly any ingredients in this sauce, so show off your good tomatoes!)
1 pound dried pasta
For the accompanying “salad”
¼ medium red onion
1 fistful soft herbs – parsley, basil, or even mint or cilantro
Mild vinegar, to taste
Salt, to taste
1. In a medium saucepan, melt the butter over medium low heat and add the onion halves, cut-side down.
2. Crush the tomatoes by hand in a mixing bowl, and don’t squirt them all over yourself. If the tomatoes are really firm and not really coming apart, chop them up or puree them. (Or puree them after the sauce is cooked if necessary, which I prefer because it also re-emulsifies the butter.) Listen to the onion start to sizzle and breathe deep, thinking, “Oh yeah, that’s what that smells like.” Scatter the crushed tomatoes around the onion, and when they’re all in there, pour in the tomato juice.
3. Turn the heat up, bringing the liquid up to simmer, then turn it down so that it cooks slowly, uncovered, with very gentle but persistent bubbles. Season lightly with salt and simmer 45 minutes, stirring occasionally.
4. While the sauce is cooking, slice the red onion as thin as you can, season it with a pinch of salt and a splash of vinegar, just enough to moisten it. Roughly chop the herbs, but don’t combine them with the onion. Look in the saucepan. As the sauce cooks, the butter will emulsify in, turning the red into more of a deep pink. After 45 minutes, the sauce should have reduced by about half, the butter will be threatening to break back out and float back to the top. The flavor will round out and deepen; and it should be sweet, tart, and buttery in equal measure.
5. Bring a large pot of generously salted water to a boil and cook the pasta ‘til al dente. As it cooks, season the sauce with salt (and maybe a pinch of sugar) to taste. Combine the chopped herbs with the red onion. Toss the cooked pasta in the sauce and serve, with a small pinch of onion salad on top or on the side. Go light on the onion salad, since you want to be able to have bites that are just pasta and sauce to revel in its loveliness.