In a large skillet, heat olive oil over low heat. Add the fennel, salt and pepper. Cook, stirring frequently, until the fennel is light brown around the edges and soft, 15 to 20 minutes. Pour in the wine. Turn up the heat and cook until the wine is evaporated, 8 to 10 minutes. Add the mustard greens and cook, stirring until wilted. Serve immediately.
c.1997, M.S. Milliken & S. Feniger, all rights reserved