Preheat a medium cooking pan over medium-low heat. Melt butter in the pan and spread it around evenly.
Place slices of bread in the pan and spread Thousand island dressing on both slices.
Squeeze liquid from sauerkraut and spread it on one slice of bread. Place two slices of Swiss cheese on the other slice of bread.
Layer corned beef over cheese evenly. Let the bread crisp and ingredients heat up. Once cheese is melted, use a spatula to carefully place one slice over the other to close the sandwich.
Cook for a couple more minutes on both sides, until bread is golden. Press gently.
Take the sandwich out of the pan, cut in half, and serve right away.
If you don't like corned beef - feel free to use turkey instead or make it with pastrami. (Note, it will taste different! But it will be delicious.)
Don't like sauerkraut? While the sauerkraut provides a delightful tangy taste and a crunch, there are many people that just don’t enjoy it. You can always omit it if you simply don’t like it OR you can substitute coleslaw or shredded lettuce.