Cook beef, bell pepper and onion in a large saucepan over medium heat, crumbling the meat with a wooden spoon, until the meat is browned, 8 to 10 minutes. Add garlic, chili powder, cumin and cayenne; cook until fragrant, about 15 seconds. Stir in salsa (or sauce) and water; bring to a simmer. Reduce heat to medium-low, cover and cook, stirring occasionally, until the vegetables are tender, 10 to 15 minutes. Stir in beans and cook until heated through, about 1 minute.