Homey Borlotti Bean Stew

In a large saucepan, heat the olive oil. Add the onion, celery and carrot and cook over moderately low heat, stirring occasionally, until lightly browned, about 20 minutes. Add the beans and prosciutto and cook until sizzling, about 4 minutes. Add the red wine and simmer over moderately high heat until almost evaporated, about 10 minutes. Add the parsley and stock and bring to a boil. Cover partially and simmer over low heat, stirring occasionally, until the beans are almost tender, about 1 1/2 hours. Uncover and simmer over moderate heat until thick, about 30 minutes longer. Discard the prosciutto, season with salt and pepper and serve.