01 - Set oven temperature to 375°F (190°C) and allow to preheat.
02 - Arrange bell peppers upright in a baking dish. Drizzle with 1 tablespoon olive oil and season lightly with salt. Set aside.
03 - Combine quinoa and vegetable broth in a saucepan. Bring to a boil, reduce heat, cover, and simmer for 15 minutes until tender and liquid is absorbed. Fluff with a fork.
04 - Heat 1 tablespoon olive oil in a large skillet over medium heat. Sauté onion for 3 minutes, add garlic, and cook for 1 minute.
05 - Stir in diced zucchini and cherry tomatoes. Cook for 5 to 7 minutes until vegetables are softened.
06 - Add cooked quinoa to the skillet with sautéed vegetables. Stir in oregano, basil, smoked paprika, salt, and pepper. Mix thoroughly and cook for an additional 2 minutes. Remove from heat.
07 - Evenly fill each bell pepper with the quinoa mixture, pressing gently to pack. Top with shredded cheese if desired.
08 - Cover baking dish with aluminum foil and bake for 25 minutes. Remove foil and continue baking for an additional 10 minutes until peppers are tender and cheese is golden.
09 - Remove from oven, garnish with fresh parsley, and serve warm.