Fagioli al Fiasco (Beans in a Flask)

There is a old method of cooking beans that traditional comes from the Tuscan region of Italy. Beans are cooked in either a earthenware pot or glass bottle which is embedded in hot ashes of the fireplace or wood burning ovens. The beans need to cook for many hours at this low temperature, simply seasoned with extra virgin olive oil and maybe fresh sage leaves. I have a Pyrex glass flask designed for this purpose and use it sometimes to cook small quantities of beans.