Cook quinoa according to package directions and set aside to cool.
Heat a grill or grill pan over medium-high heat. Mix together the salt, chili powder and cumin and rub on chicken. Grill chicken on both sides until cooked through; set aside to cool, then slice.
Make chipotle lime vinaigrette: Whisk together the lime juice, garlic, honey, adobo sauce, salt and olive oil. Then discard halved garlic cloves.
Peel Wonderful Halos mandarins and separate segments.
Spoon quinoa into 4 bowls. Top each bowl with some spinach, black beans, bell pepper, avocado, Wonderful Halos mandarin segments and sliced chicken. Drizzle each with vinaigrette and sprinkle with scallions to serve.