Start by washing the bell peppers and cutting off their tops. Remove the seeds and membranes carefully to create space for stuffing. Arrange them upright in a baking dish so they stay stable while filling.
Heat olive oil in a pan and sauté onions until soft and translucent. Add garlic and cook briefly until fragrant, then mix in cooked rice, olives, herbs, and spices. Turn off heat and stir in feta, mozzarella, and parsley for a rich, cheesy mixture.
Spoon the prepared filling into each pepper generously, pressing lightly to pack it in. Make sure each pepper is filled evenly to ensure consistent cooking. Sprinkle a little extra cheese on top for a golden finish.
Preheat your oven to 180°C (350°F) and cover the dish with foil. Bake for about 25 minutes, then remove the foil and bake for another 10–15 minutes until the tops are slightly golden and peppers are tender.
Once baked, let the peppers cool for a few minutes before serving. This helps the filling set slightly and makes them easier to handle. Serve warm and enjoy the rich Mediterranean flavors.