Heat the oil in a large Dutch oven over medium heat. Add the onion and bell pepper and cook, stirring occasionally, until the vegetables are soft, about 10 minutes. Add the cumin, chili powder, oregano, and minced garlic then cook, stirring constantly, for 1 minute.
Add the ground beef, breaking up the meat, until the meat is no longer pink. Stir in the tomatoes, beef broth, chipotle and adobo sauce, sea salt, and freshly cracked pepper, to taste. Simmer, partially covered, stirring occasionally, for 30 minutes.
Stir in the beans and cook, partially covered, 20 minutes longer. Taste and re-season if needed. Ladle into bowls and top with sour cream and green onions. Enjoy.