Preheat oven to 220°C / 430°F.
Grate the tomato insides and the ripe tomato for the filling into a large mixing bowl using a box grater.
Add the remaining ingredients for the filling, season with salt and pepper, and mix well.
Hollow the eggplant the same way you did the zucchini.
Stuff each vegetable using a spoon. Stir the filling after stuffing each vegetable and try to distribute it evenly to all the vegetables. Put the tops back on.
Peel the potatoes, rinse, cut them into thick wedges, then cut each wedge in half.
Add the potatoes all around the veggies to hold them in place.
Drizzle with olive oil on top of the veggies. Season them with salt and pepper. Add also a splash of water to the pan.
Bake for about 1 hour. After the first 20-25 minutes of baking, carefully cover with aluminum foil, to prevent veggies from burning on top. You can taste the rice to see if it's done. If there's still too much water in the pan, uncover it and give a final roast for about 10 minutes.