Heat 1/2 Tbsp. oil in a large saucepan over medium heat; add chicken and salt to pan. Cook chicken, stirring to break up meat, until it is crumbly and no longer pink, about 5 minutes. Using a slotted spoon, transfer chicken to a plate.
Add remaining oil, garlic, onion, chili powder and cumin. Cook, stirring often until onion is tender, about 7 minutes. Stir in broth, tomatoes and tomato paste and bring to a boil. Reduce heat and simmer for 15 minutes. Stir in pepper strips and beans and simmer, stirring occasionally, until sauce is thick, about 10 minutes. Return chicken and any of its juices to saucepan and cook for 1 minute to heat through.
Serve with cheese, scallions and tortilla chips, if desired.