Rinse beans and place in a large bowl. Cover with cold water and soak at room temperature for at least dozen hours. Heat oil in an 8 to 9 litre pan over medium heat. When oil is hot, add bacon and cook until lightly browned. Add chiles, onion, and garlic and continue to cook, stirring until vegetables are soft (about 5 minutes). Add beans, beer, broth, tomato sauce, oregano, and cumin; bring to a boil, stirring. Reduce heat, partially cover pan, and simmer, stirring often, until beans are tender and most of the liquid is absorbed (about 2.5 hours). Makes 8 to 10 servings.