Prepare the Pork: Pat the pork tenderloin dry with paper towels. This helps the marinade adhere better and promotes a nice sear later on.

Whisk Together Marinade Ingredients: In a medium-sized bowl, combine the soy sauce, olive oil, honey (or maple syrup), minced garlic, Dijon mustard, Worcestershire sauce, rosemary, thyme, black pepper, and optional red pepper flakes. Whisk vigorously until all ingredients are well combined and the honey/syrup is fully incorporated.

Marinate the Pork: Place the trimmed pork tenderloin in a resealable plastic bag or a shallow dish. Pour the prepared marinade over the pork, ensuring it is evenly coated. Seal the bag or cover the dish, pressing out as much air as possible.

Refrigerate and Marinate: Place the pork in the refrigerator to marinate for at least 30 minutes, or for optimal flavor, marinate for 2 to 4 hours. Avoid marinating for much longer than 4 hours, as the enzymes in the soy sauce can start to break down the pork's texture.

Cook the Pork: Once marinated, remove the pork from the marinade. Discard the remaining marinade. Cook the pork tenderloin using your preferred method: grilling, roasting in the oven at 400°F (200°C) for 20-25 minutes, or pan-searing over medium-high heat for about 15-20 minutes, turning occasionally, until the internal temperature reaches 145°F (63°C).

Rest and Serve: Let the pork tenderloin rest for 5-10 minutes before slicing. This allows the juices to redistribute, resulting in a more tender and moist final product.