Pour 3 cups (750 mL) cold water in a saucepan. Add chicken, garlic, ½ tsp (2 mL) of the salt, the coriander and cumin; bring to a boil over medium-high heat. Reduce heat to medium-low and simmer until chicken is no longer pink inside, 12 to 15 minutes. Using tongs, transfer chicken to a bowl and let cool enough to handle.
Meanwhile, add sweet pepper to cooking liquid; cook for 2 minutes. Strain, reserving both cooking liquid and pepper mixture.
Measure and pour 2 cups (500 mL) of the reserved cooking liquid back into saucepan (reserve any remaining for another use or, alternatively, add enough water as necessary to make 2 cups/500 mL); stir in quinoa and bring to a boil. Reduce heat, cover and simmer until no liquid remains and quinoa is tender, about 15 minutes. Remove from heat and stir in black beans and reserved pepper mixture; set aside.
Meanwhile, in a small saucepan, combine tomatoes, vinegar, honey, dry mustard, chili powder and remaining salt; bring to a simmer over medium heat, stirring occasionally. Reduce heat to medium-low, cover and continue simmering for 5 minutes, stirring occasionally. Remove from heat. Shred or slice chicken; add to sauce. Divide quinoa mixture among serving bowls. Spoon chicken mixture over top. Top with corn, avocado, cheese, onion and cilantro.
Per Serving:328 calories, 24 g protein, 10 g fat (3 g saturated fat), 38 g carbohydrates, 8 g fibre, 42 mg cholesterol, 407 mg sodium