Preheat the oven to 350°F. Combine all the 'Thousand Island Dressing' ingredients in a glass jar, put a lid on it and seal it tightly, and shake real good until everything is combined. Set aside.
Strain any extra liquid out of the sauerkraut and squeeze dry with paper towels. Set aside.
Carve up the corned beef into bite-sized pieces. Try not to eat it all before it makes it into the casserole dish. Place the corned beef pieces in the bottom of a 9x13 baking dish.
Evenly distribute the sauerkraut over the corned beef and drizzle about half of the Thousand Island Dressing over that. Cover the top with the Swiss cheese and sprinkle on the caraway seeds, if using.
Bake in the preheated oven for 15 minutes, or until the top is bubbly and slightly golden. Remove from oven and serve hot with an additional drizzle of the remaining Thousand Island Dressing.