The most traditional way to cook sauerkraut with potatoes is to add oil to a pan and fry up some onions within the pan. Then add salt and pepper to taste. Next add thinly sliced potatoes to the pan and fry those with the onions until they become golden brown. The next step in cooking traditional sauerkraut with potatoes is to slowly add the sauerkraut to the pan and stir everything together. Serve the vegetables hot. If there is too much liquid within the pan, then drain it from the mix.