Trim the tenderloin roast of fat and silver skin (see photo on left). Silver skin is a silvery-white connective tissue. It does not dissolve when the tenderloin is cooked, so it needs to be trimmed away. If the silver skin is not trimmed off, it will cause the tenderloins to curl up into the shape of a quarter moon.
Score the meat at various points across the width of the tenderloin and set aside.
In a small bowl, combine soy sauce and ground mustard. Using your fingers, rub the soy/mustard mixture onto the roast. On a piece of wax paper, combine fennel seeds and caraway seeds; roll the coated roast in the seed mixture to coat evenly. Wrap tightly in plastic wrap and refrigerate at least 2 hours or overnight.
Preheat oven to 375 degrees F. Bring roast to room temperature before cooking. Unwrap plastic wrap from the roast.
Place fat side up onto a rack in a shallow baking pan. Bake, uncovered, 30 to 45 minutes or until a meat thermometer inserted into thickest part of the roast registers 140 degrees F. to 145 degrees F.
Remove from oven and transfer onto a cutting board; let roast stand 15 minutes before carving (meat temperature will rise 5 to 10 degrees after it is removed from the oven). Transfer onto a serving platter and serve with Savory Mustard Sauce.
In a small saucepan over medium heat, combine water, ground mustard, and cornstarch. Stir in corn syrup and cider vinegar; cook and stir until thickened and bubbly. Cook and stir another 2 minutes. Remove from heat and let cook before using.
* For a more flavorful and succulent pork roast, brine your pork roast according to my Guidelines for Brining Pork. Most cooking experts agree that brined poultry and meat are more flavorful and succulent. The results are particularly apparent when the meat is cooked in the smoky heat of a covered barbecue, because the brine helps to mask bitter components in smoke that can make foods taste unpleasantly acrid.
Petite Pork Tenderloin Roast Recipe: https://whatscookingamerica.net/pork/petiteporkroast.htm