Peel the potatoes and cut them lengthwise. Cut the onions and carrot finely. Dice the tomato.
Put oil in a pot and once it heats up, throw in the onions and carrot to braise. Next, add the potatoes and pour in enough water to almost cover them. Leave them to saute with the lid closed.
Heat oil in another container and put paprika in it. Stir well until the paprika dissolves. Then pour it into the potatoes. If desired, you can sprinkle on more if it's not enough, or add a little tomato paste.
Once the potatoes are nearly ready, sprinkle on the spices and add the tomato. If there's too much water, leave the pot to boil without the lid.
Once ready, pour it into an oven dish and bake at 356°F (180 °C).