Yuba Pappardelle with English Peas, Fava Leaves, and Basil

In 10-inch sauté pan over moderately high heat, bring vegetable stock and salt to boil.

Add peas and simmer, uncovered, until bright green and almost tender, 1 to 2 minutes.

Transfer peas and cooking liquid to blender and blend on high until very smooth, about 1 minute. Set aside. (Purée can be made ahead and refrigerated, tightly wrapped in plastic wrap, up to 12 hours. To maintain peas' vibrant green color, cool purée over ice bath before refrigerating.)

In medium saucepan over moderate heat, stir together buttermilk, yuba, peas, and 1/4 teaspoon salt. Bring to simmer, then reduce heat to low, cover, and cook until peas are just tender, about 2 minutes. Stir in pea purée and fava leaves, cover, and cook until fava leaves are wilted, about 30 seconds.

Remove from heat and stir in basil, remaining 1/4 teaspoon salt, and pepper.

Serve immediately.

•Yuba is available at many Asian markets. If you can't find it fresh or frozen, you can substitute dried—six sheets will be about one ounce. Soak the dried strips in warm water for ten minutes and then drain them well before adding to the buttermilk.•If you don't want to make your own buttermilk, you can substitute regular whole milk. Do not substitute commercially made buttermilk, which is cultured and has a sour flavor.•Fava leaves are the leaves of the plant that produces fava beans. They're generally available in markets in the spring. Other fresh spring greens, such as pea shoots or baby spinach, can be substituted.