Heat a large griddle or skillet over medium heat. Coat with non stick spray.
Working in batches, add 2 stacks on sliced corned beef {2 slices each}.
Top each stack with 2-3 tbsp of drained sauerkraut.
Then add a slice of Swiss cheese to each.
Cover the skillet with a lid and let the meat and cheese steam and melt for 1 min.
Spread 1000 Island dressing on the inside of a large spinach tortilla.
Using a spatula remove a corned beef stack from the skillet and place on the tortilla.
Push the meat to one side of the tortilla.
Now, roll the tortilla in on that side and fold in the corners until you have a sealed burrito.
Slice, secure with toothpicks, and serve.