Peel the potatoes and cut into chunks. Peel onions and cut in half. Mushrooms are cleaned and cut into slices. The carrot is cut according to taste. Vegetables are placed in a greased tray. Add salt, sprinkle with salt universal spice, pepper and spice ready for potatoes. Sprinkled with oil, and water to cover the potatoes until about 1/3. Bake in preheated oven until the potato is ready.