Put all the ingredients in a wide 6-to 7-quart heavy pot (don't worry if the pork is not completely covered with water) and bring to a boil, skimming the surface as necessary. Lower the heat, cover, and simmer vigorously, stirring occasionally, until the pork is fork-tender, about 1½ to 2 hours. Discard the orange pieces and bay leaves. Transfer the pork pieces to a bowl, cover, and let the liquid continue to reduce, about 10 minutes.