Preheat the oven to 375°F (190°C). Cut the tops off the tomatoes, bell peppers, and zucchini (or eggplant), then carefully scoop out the insides, leaving the skins intact. Set the vegetable shells aside.
- In a large saucepan, heat 2 tablespoons olive oil over medium heat. Add the chopped onion and garlic and sauté until softened, about 3-5 minutes. Stir in the rice, oregano, basil, and cinnamon (if using). Add the diced tomatoes, tomato paste, and the scooped-out tomato and zucchini pulp. Stir to combine.
- Pour in the vegetable broth and season with salt and pepper. Bring to a simmer, then reduce heat and cover. Cook for 10-12 minutes until the rice absorbs most of the liquid and is partially cooked. Remove from heat, stir in parsley or dill, and crumbled feta (if using).
- Carefully stuff each vegetable shell with the rice mixture, pressing gently. Arrange the stuffed vegetables in a baking dish and drizzle with olive oil. Season with salt and pepper.
- Cover the dish with aluminum foil and bake for 45-50 minutes until vegetables are tender and the rice is fully cooked. Remove the foil for the last 10 minutes to allow the tops to brown.
- Serve with a side of crusty bread and a squeeze of lemon for freshness.