Soak black beans in water overnight. Drain and place in saucepan. Add water and simmer for 30 minutes. Remove from heat. Do not drain. Heat oil in saute pan over medium-high heat. Saute onion, garlic, and chilies until onion is tender. Add to beans, then add rice, salt, cumin, chipotle powder, and pepper. Increase heat to medium-high and cook until most of the water is gone. Reduce to lowest heat and cover. Cook until rice is tender, about 20 minutes.