Rinse quinoa under cold water and drain. Place quinoa and water in a small saucepan. Bring to a boil, reduce to a simmer, cover and cook 10 minutes, or until water is absorbed. Transfer to a large bowl to cool slightly.
Meanwhile, preheat oven to 400 degrees.
Cut each zucchini in half horizontally, then scoop out the seeds. If they don’t lie flat, trim a thin strip from the bottom. Place them on a baking sheet or in a 9x13 casserole dish.
Combine cooked quinoa with garlic powder, oregano, red pepper, red onion, olives, chickpeas, feta, olive oil, lemon juice and lemon zest. Season with salt and pepper, to taste.
Bake until the zucchini is tender, about 12-18 minutes. Serve immediately, garnished with chopped parsley, if desired.