Add the Dijon mustard, egg yolk, and lemon juice to a mixing bowl and whisk together until smooth.

Slowly incorporate the olive oil into the mixture, whisking small amounts of it in at a time until it is completely incorporated. Whisk vigorously until mixture is thick and creamy.

Add the stone ground mustard

Put your oven on the high broil setting.

Place slices of bread on a baking sheet and place on the top (or second to the top) wrack in your oven. Bake for 2 to 3 minutes, or until bread reaches desired crisp.

Remove from the oven and flip all slices of bread over. Add sliced or grated Swiss cheese to half of the slices of bread, and place back in the oven for 3 minutes or until cheese has melted and bread is toasted.

Add desired amount of turkey pastrami meat, sauerkraut, and mustard aioli to each sandwich.

Slice sandwiches in half and devour.