Make the Russian dressing by mixing all ingredients in a bowl. Season with salt and pepper and chill in the fridge until ready to use.
Layout the slices of Stonemill Bakehouse Sourdough Multigrain Rye bread on a tray or cutting board and spread about a tbsp of Russian or Thousand Island dressing on each one.
Then top half the bread pieces with a slice of Swiss cheese.
Divide and layer the corned beef or Pastrami on top of the cheese.
Spoon about 2 tbsp of sauerkraut over the corned beef.
Add the rest of the Swiss cheese slices.
Top with the remaining slices of bread. Butter the outside slice.
Heat a large cast iron pan or skillet on medium to medium low and place the sandwich -buttered side down-and cook until golden (if using a Panini press, butter both sides before placing sandwich in the machine).
Before turning, butter the top slice of bread, then flip sandwich and cook until golden and cheese has melted.