Preparation

法瓦斯（Parboil）：

• To parboil fava beans, you’ll need just four basic kitchen tools: a medium-large pot (like a Dutch oven or soup pot, 4-quart capacity is fine), a large work bowl, a mesh strainer, and a clean dishtowel or two. Fill the pot with 2 quarts water and 1 Tbs. coarse salt and bring it to a boil. Fill the work bowl mostly with ice and cover with cold water. Dump your beans into the boiling water and cook for 2 minutes (for small favas) to 3 minutes (fro older, larger favas). Begin timing as soon as the vegetables are in the water; don’t wait for it to return to a boil. And don’t go anywhere—use your mesh strainer to transfer the beans to the ice bath just as soon as the time’s up. Let the beans sit for a minute or two in the ice water to stop the cooking and cool down. Lift the vegetables (use your hands or the strainer again) out of the ice bath and let them drain well in one layer on a dishtowel (or paper towels). Slip the beans out of their skins (see photo) and store them in a shallow container (lined with paper towels to absorb any excess moisture), covered with a slightly damp paper towel or dishtowel. They’ll keep in the refrigerator overnight. If you plan to use them right away, make sure they’re very dry.

  
  Slip a fava bean out of its skin by pinching one end of the parboiled bean with a thumbnail. Squeeze, and out pops the bean.

• In a medium skillet, heat the olive oil over medium heat. Add the prosciutto and sauté for 1 minute. Add the garlic and sauté, stirring constantly, until it’s very fragrant and just beginning to turn brown, another 1 to 2 minutes. Add the fava beans, season with the salt, and sauté until the favas are heated and coated well with the pan contents, another 2 minutes. (Some of the beans will begin to turn a lighter color.) Add the balsamic, turn off the heat, and stir to coat. Add the mint and stir to combine and wilt it. Taste for salt; depending on the saltiness of your prosciutto, you might want to add more.