Those who do not like tomatoes can leave them out, and the dish will still be very savoury. The potatoes should be peeled, washed, and cut into thin slices, and the onions peeled and cut into thin slices. Arrange the vegetables and tomatoes in layers; dust a little pepper and salt between the layer, and finish with a layer of potatoes. Cut the butter into little bits, place them on the top of the potatoes, fill the dish with hot water, and bake the hot-pot for 2 hours or more in a hot oven. Add a little more hot water if necessary while baking to make up for what is lost in the cooking.