Wash the potatoes, peel and chop them. Chop the onion and braise it in heated oil.
Once the onion softens, add the potatoes and braise them lightly, about 3-4 min.
Next, pour the water mixed with the tomato paste in a pot, add the potatoes and onion, leave them to boil until softened.
Season the dish with the spices to taste. Finally add the chopped tomatoes and leave to boil for another 2-3 min. before removing from the stove. Serve.