Combine beans and water in large pot. Bring to a boil over high heat. Reduce heat and simmer 2 minutes. Remove from heat. Cover and let stand 1 hour. Meanwhile, cook chorizo over medium heat in skillet until brown, breaking up as little as possible. Drain and set aside. When beans are finished soaking, drain and return to pot. Add beef broth, pork, onions, garlic, bay leaf and oregano. Bring to a boil. Reduce heat and simmer 1 hour. Add chorizo, salt and pepper and simmer, uncovered, until beans are very tender and broth thickens slightly, about 20 minutes, stirring occasionally. Remove bay leaf.