oil in a large frying pan, and once hot, add the onions. then add potatoes. after a couple of minutes, turn potatoes so they brown on both sides. add some water once they are brown, and sprinkle with paprika. cook for around 20 minutes, adding water when necessary. you don't want it to burn, but you don't want it to be too soupy either. cook until potatoes are soft when you poke them with a fork. sprinkle with salt and pepper before serving.
*you can also cook them with some peppers or garlic if you like. 