Rinse quinoa well under cold running water. Cook according to package directions.
Meanwhile, heat oil in a large skillet over medium-high. Add onion and bell pepper, and cook, stirring occasionally, until onion is almost translucent, about 5 minutes. Add turkey, cumin, salt, chili powder, and black pepper; cook, stirring occasionally, until browned and vegetables are tender, about 5 minutes.
Stir in salsa and broth; cook, stirring occasionally, until liquids reduce and turkey mixture is well coated in salsa mixture, 3 to 4 minutes.
Serve over quinoa divided evenly among four bowls. Top with avocado, tomatoes, cabbage, cheese, and sour cream, if using.
