1. Lay out two slices of rye bread on a cutting board.
2. Top first piece of bread with one slice of Muenster cheese, then about 2 ounces of sauerkraut, 4 ounces (or roughly three to four thin slices) of pastrami, and a second slice of Muenster cheese. Set aside.
3. Spread second piece of bread with Thousand Island dressing, then place on top of the other half of the sandwich.
4. Brush top and bottom of sandwich with butter.
5. If you own an electric sandwich maker or Panini press, place sandwich inside for 2 1/2 to 3 1/2 minutes. If you don't have a sandwich press, simply place sandwich in a sauté pan on top of your stove, set at medium heat. Cook for 3 1/2 to 4 1/2 minutes on each side.
6. Remove sandwich and while still hot; cut in half and serve.