Using a small sharp knife cut a small, deep X in the bottom stem of each sprout. Bring a large pot of lightly salted water to a boil over high heat. Add the sprouts anda cook until barely tender, about 8 minutes. Drain and rinse well under cold running water. Drain well, pat dry and cut the larger sprouts into halves or quarters.

In a large skillet, heat the oil over medum heat. Add the prosciutto and cook until very lightly browned, about 3 minutes. Add the brussels sprouts, roasted chestnuts and stock and bring to a boil over high heat. Cook, stirring often, until the stock has evaporated, about 5 minutes. Season with salt and pepper. Transfer to a warmed serving dish and serve hot.

Note: These ingredients are very full flavored so serve in small portions.