Preheat oven to 350 degrees F. Prepare a rimmed baking sheet by lining it with parchment paper, and set aside.
Drain the sauerkraut well.
Using a small paring knife, trim any "tough" crusts or uneven edges from the bread. Stack the trimmed slices of bread on a microwave-safe plate.
Microwave trimmed bread for 5 – 8 seconds to warm and soften (repeat as needed; leave bread in microwave until ready to use). Remove one slice at a time to roll and assemble.
TO ASSEMBLE:
Using a rolling pin, roll each slice of bread individually until flat (like a tortilla).
Thinly spread Reuben Sauce (or dressing) on rolled bread, leaving 1/2-inch DRY around the edges.
Starting at the long/wide end of bread closest to you, add a single layer of Swiss cheese on the lower half of the bread. Then add a single layer of pastrami over that, and finally a couple of tablespoons or sauerkraut. Make sure to layer ingredients on just 3/4 of the piece of bread so everything stays inside the roll when you roll it up.
Place rolls – open edge down – on the baking sheet, leaving an inch of space between each roll. Bake for 5 minutes, then turn the rolls and bake for an additional 5 minutes.
Serve warm with additional Reuben Sauce or prepared dressing.
*It’s very important that the bread you use is “squeezably soft” because dryer, coarse breads don’t roll out well.
*Warming the bread in the microwave softens the bread even further so it rolls out to a thin tortilla-like consistency. Don’t over-warm the bread, or allow it to cool completely before rolling. Keep the bread in the microwave until ready to roll.
*If making ahead, roll the slices of bread and place in an air tight container for up to a day before making Reuben rolls.
*Lacey, or Lacy, Swiss is a U.S.-made Swiss cheese that has a unique “lace” pattern. Its delicate flavor and wonderful melt-ability make it a great choice for sandwiches, wraps and Pumpernickel Reuben Rolls! "Regular" Swiss cheese slices will also work well.
*IF MAKING AHEAD: (1) Make sure sauerkraut is completely drained so it doesn’t saturate the rolled bread. (2) Cover and refrigerate until ready to bake. (3) Add 5 minutes baking time to allow cold rolls to warm through.
*TO RE-WARM REUBEN ROLLS: Microwave for 20 – 30 seconds, or bake in a 350 degree oven for 3 - 5 minutes. Microwaving will merely warm the rolls, while baking will create a slightly crispy exterior.