Using a paring knife, poke 3 small slits into each potato. Bake in the oven for 1 hour and 15 minutes. Remove the potatoes from the oven and turn the oven temperature up to 425 degrees F. Let the potatoes cool for 5 minutes.
Using a fork punch some holes in the top of each potato. Press inward on the ends of each potato so that the tops break open. Divide the apple sauerkraut evenly between the potatoes and then top them with the sausage and Cheddar. Arrange the potatoes on a sheet pan and bake until the cheese is melted, about 5 minutes. Remove from the oven to a serving platter and serve.