Step 1: Preheat your oven to 375°F (190°C). Lightly grease a 9x13 inch baking dish.
Step 2: Unroll one can of crescent roll dough. Carefully lay the dough in the prepared baking dish, pressing the seams together to form a solid bottom crust that extends slightly up the sides.
Step 3: Spread about half of the Thousand Island (or Russian) dressing evenly over the crescent roll crust.
Step 4: Evenly layer the sliced or shredded corned beef over the dressing.
Step 5: Spread the well-drained sauerkraut over the corned beef. Remember, draining it thoroughly is key!
Step 6: Top the sauerkraut with the sliced Swiss cheese. Arrange the slices to cover the sauerkraut as much as possible.
Step 7: Drizzle the remaining Thousand Island dressing over the Swiss cheese layer.
Step 8: Unroll the second can of crescent roll dough. Carefully place it over the cheese and dressing layer, pressing the seams together to form a top crust. Pinch the edges of the top and bottom crusts together to seal.
Step 9: If desired, brush the top of the crescent dough with a little melted butter or an egg wash for an extra golden finish. You can also sprinkle with a pinch of caraway seeds for a more authentic rye bread flavor.
Step 10: Bake for 20-25 minutes, or until the crescent rolls are puffed, golden brown, and the cheese is bubbly and melted.
Step 11: Remove from the oven and let it rest for 5-10 minutes before slicing and serving. Enjoy!