To prepare pickles, combine 1/4 cup water, vinegar, and sugar in a medium microwave-safe bowl; microwave at HIGH 2 minutes or until boiling. Stir in onion. Remove from heat; let stand 20 minutes at room temperature. Drain.
To prepare sauce, combine yogurt, tahini, juice, and 2 tablespoons water in a small bowl, stirring well with a whisk. Refrigerate until ready to use.
To prepare bowls, combine quinoa and 1 teaspoon oil in a medium bowl; toss to coat. Add kale and 1/2 cup parsley. Toss to combine.
Combine onion powder, garlic powder, oregano, cumin, salt, and pepper in a small bowl. Heat a large skillet over medium-high heat. Add remaining 1 teaspoon oil to pan; swirl to coat. Sprinkle chicken evenly with spice mixture; gently pat onto chicken (chicken will be heavily coated). Add chicken to pan; cook 4 minutes or until golden brown. Turn and cook 2 minutes or until done. Let stand 5 minutes. Thinly slice chicken.
Preheat broiler to high.
Arrange pita triangles in a single layer on a baking sheet; coat pita evenly with cooking spray. Broil 1 to 2 minutes on each side or until crisp.
Place about 3/4 cup quinoa mixture in each of 4 bowls. Top each serving with 1/4 cup tomatoes, 1/4 cup cucumber, 2 tablespoons chickpeas, one-fourth of olives, one-fourth of cheese, one-fourth of pickled onion, and one-fourth of sliced chicken. Drizzle evenly with yogurt mixture. Top evenly with pita wedges. Sprinkle bowls evenly with remaining 1/4 cup parsley.