Step 1

Preheat your oven to 425°, and place a wire rack over a foil-lined baking sheet.

Step 2

To a small ramekin, add 1 1/2 teaspoons of salt, 1/2 teaspoon of black pepper, the granulated onion and garlic, the Italian seasoning and the ground caraway seeds; set these dry rub ingredients aside for a moment.

Step 3

Place your pork tenderloin on a work surface (or into a large bowl) and drizzle a teaspoon or two of the oil over; rub the spicy brown mustard all over it, and sprinkle the dry rub evenly over, as well, rubbing it in.

Step 4

Place the tenderloin onto the wire rack, and roast for about 40-45 minutes, or until a digital thermometer inserted into the thickest part registers 155° (as the meat rests the temp will come up slightly more).

Step 5

While the tenderloin roasts, add the butter to a large, heavy bottom pan (I love my cast iron skillet for this) set over high heat; once melted, add in the sliced onions along with a couple of good pinches of salt and pepper, and stir the onions around occasionally, allowing them to caramelize for about 10-12 minutes, or until golden.

Step 6

Then, add in the beer, and allow it to vigorously bubble and boil, reducing down for about 5 minutes, until the onions are glossy and have a jam-like consistency; set onions aside and keep warm.

Step 7

Once the tenderloin has roasted, allow it to rest for 10 minutes, then slice thinly.

Step 8

To assemble the sandwiches, spread some of the mayo and the mustard on the bottom of the roll, add some slices of pork tenderloin, and top with a slice of Swiss cheese; place under the broiler for a couple of minutes until melted.

Step 9

Next, top with a couple of tablespoons of the beer-braised onions and about 1/4 cup of the sauerkraut, spread some mayo and mustard on the top roll to cover, and enjoy.