Make the Thousand Island dressing by simply whisking the dressing ingredients, mayo, sour cream, ketchup, sugar, vinegar, onion powder, and minced pickles together in a small bowl. Set aside.
Heat up your broiler to high and get a pan ready to place the bottom parts of the sandwiches on to go under the broiler.
I prefer to make this sandwich with pre-toasted bread under the boiler instead of in a skillet on the stove because it's a messy sandwich to try to flip.
Toast the rye bread in a toaster.
Line a baking sheet with the bottom part of the sandwiches.
Spread the bottom bread slices with dressing.
Top with sliced or shredded leftover turkey.
Top the turkey with Swiss cheese slices.
Place the pan in the oven under the broiler until the cheese melts. Keep an eye on them, as this happens fast.
Top melted slice of Swiss cheese with a mountain of sauerkraut.
Spread dressing on the top slice of toasted rye bread and place it on top of the sauerkraut!
Serve immediately with pickle spears on the side!