Cut the tops off the bell peppers and remove the seeds and membranes. Place them upright in a baking dish.
In a medium saucepan, combine the rinsed quinoa and vegetable broth. Bring to a boil, then reduce heat to low, cover, and simmer for about 15 minutes, or until all the liquid is absorbed.
In a large mixing bowl, combine the cooked quinoa, cherry tomatoes, chickpeas, olives, feta cheese, parsley, oregano, garlic powder, olive oil, lemon juice, salt, and pepper. Mix well to combine all the flavors.
Carefully stuff each bell pepper with the quinoa mixture, pressing down gently to pack it in.
Cover the baking dish with aluminum foil and bake in the preheated oven for 30 minutes.
Remove the foil and bake for an additional 10-15 minutes, until the peppers are tender and the filling is heated through.
Remove from the oven and let cool slightly before serving.
Notes
Serve warm, drizzled with extra olive oil and garnished with parsley.