Heat olive oil in a nonstick pan; cook and stir red onion, cilantro, garlic, and chili powder until onion is softened, about 5 minutes. Cook and stir pinto beans and about 2/3 cup chicken broth into onion mixture until heated through, about 5 minutes. Mash pinto beans with the back of a spoon. Add remaining chicken broth and simmer until desired consistency.