Makes: 4 servings | Time: 30 minutes
4 tablespoons olive oil
1 pound cremini mushrooms, sliced
1 large or 2 small leeks, trimmed, well rinsed, and chopped
4 garlic cloves, sliced
1½ pounds lacinato kale, rinsed and chopped (stems included)
1 teaspoon paprika
½ cup dry white wine or water
2 cups vegetable stock, or water, or more as needed
2 tablespoons Dijon mustard
12 ounces wide, flat whole wheat pasta
1½ cups cooked cannellini beans, with some of the cooking liquid
Bring a large pot of water to a boil and salt it. Put the oil in a large skillet over medium heat. When it’s hot, add the mushrooms, sprinkle with salt and pepper, and raise the heat to medium-high. Cook, stirring occasionally, until they release their liquid and the pan begins to dry, 8 to 10 minutes.
Add the leek and garlic and sprinkle with salt and pepper. Cook, stirring often, until soft, 3 to 5 minutes. Add the kale and paprika, toss to coat, then pour in the wine and cook, scraping any browned bits off the bottom of the pan, until the wine has reduced by half, just a minute or 2.3. Add the stock and the mustard and bring to a boil. Adjust the heat so the mixture bubbles gently, and cook, stirring occasionally, until the kale stems are soft and the leaves are silky, 10 to 15 minutes.
Meanwhile, add the pasta to the boiling water, and cook, stirring occasionally, for 5 minutes, then start tasting. When the pasta is tender but still has some bite, scoop out 1 cup of the cooking water, then drain.
Put the beans in a food processor with a spoonful or so of the cooking liquid from the pot; puree until smooth. When the kale is ready, stir in the beans. If the mixture is too thick, add more stock ¼ cup at a time, stirring after each addition. Cook, stirring frequently, until the sauce is warmed through. Taste and adjust the seasoning, and serve hot, spooned over the pasta.