In the meantime, add frozen edamame to a skillet over medium-high heat. Cook, stirring occasionally, 7 minutes, or until water is absorbed and edamame start to brown in places. Turn off heat.
Stir cooked quinoa, cooked edamame, cabbage, baby spinach, carrots, peanuts, and jalapeño (if using) in a serving bowl or dish.
Cover and refrigerate up to 3 days.
Gluten-free variation: use gluten-free tamari or liquid aminos instead of soy sauce.