Prep Time: 25 Minutes
Cook Time: 1 Hours
Total Time: 85 Minutes
1. Preheat your oven to 425° and place a wire rack over a foil-lined baking sheet.
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.
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.
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).
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.
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.
7. Once the tenderloin has roasted, allow it to rest for 10 minutes, then slice thinly.
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.
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.