Heat oil in large pot over medium; cook onion and bell pepper 5-6 minutes until softened.
Add garlic, cumin, paprika, chili powder, and cayenne; stir constantly 1 minute until fragrant.
Add beans and broth; boil, reduce heat, and simmer 20 minutes to blend flavors.
Mash about half the beans against pot side with masher or wooden spoon back to thicken, leaving some whole.
Add lime juice; season with salt and pepper. Thin with broth or water if needed.
Serve hot with sour cream, cheese, avocado, cilantro, and tortilla chips.