In a medium saucepan, combine the rinsed quinoa and water or broth. Bring the mixture to a boil, then reduce the heat to low, cover, and simmer for about 15 minutes or until the liquid is fully absorbed. Remove from heat and let it sit for 5 minutes before fluffing with a fork.
While the quinoa cools slightly, whisk together the olive oil, apple cider vinegar, honey, Dijon mustard, salt, and pepper in a small bowl. Whisk vigorously until the dressing is emulsified and smooth.
In a large mixing bowl, combine the fluffed quinoa, cooked chicken, dried cranberries, diced apple, minced red onion, and toasted pecans. If you are using kale, you can add it now; if using spinach, wait until just before serving to keep it crisp.
Pour the prepared dressing over the salad mixture. Gently fold everything together until all ingredients are evenly coated. Taste and add extra salt or pepper if needed.
Add the fresh greens to the bowl and give it one final, gentle toss. Serve immediately while slightly warm, or refrigerate for an hour to let the flavors meld together.