1. Cook the waffle fries according to package directions.
  2. In a bowl, toss together swiss and cheddar.
  3. On a baking sheet or in a large cast iron skillet, spread half the waffle fries in an even layer. Top with half the cheese mixture, half the sauerkraut and half the corned beef. Repeat a second layer on top.
  4. Preheat the broiler.
  5. Broil the nachos until cheese is bubbling, about 5 minutes.
  6. Drizzle Thousand Island over top and garnish with chives.
  7. Serve immediately.