Trim silver skin and excess fat from the pork tenderloin. If the tenderloin is uneven in thickness, lightly pound with a meat mallet to an even thickness so it cooks uniformly (about 1 to 1 1/2 inches thick).

Prepare Marinade

In a medium bowl, whisk together olive oil, soy sauce, Dijon mustard, honey, lemon juice, minced garlic, chopped rosemary, salt, and 2 tsp of the black pepper until smooth and emulsified.

Marinate

Place the tenderloin in a resealable plastic bag or shallow dish. Pour the marinade over the pork, turning to coat evenly. Seal or cover and refrigerate for at least 30 minutes and up to 4 hours. (If short on time, 15–20 minutes at room temperature will still add flavor.) Remove pork from refrigerator 20 minutes before cooking to come closer to room temperature.

Preheat and Season

Preheat the oven to 400°F (205°C). Remove the pork from the marinade and let excess drip off. Pat the pork lightly with paper towel (this helps with browning). Season all sides with the remaining 1 tsp black pepper and, if needed, a light additional pinch of salt.

Sear

Heat a large ovenproof skillet over medium-high heat until hot. Add 1 tbs olive oil (or a neutral oil). When shimmering, place the tenderloin in the skillet and sear without moving for 2–3 minutes until a deep golden-brown crust forms. Turn and sear the other sides, rotating to get an even crust (about 6–8 minutes total searing time).

Roast

Transfer the skillet with the seared pork to the preheated oven. Roast until an instant-read thermometer inserted into the thickest part registers 140°F (60°C) for medium doneness (about 12–15 minutes, depending on thickness). For slightly more done, cook to 145°F (63°C). Remove from oven and tent loosely with foil. Let rest 8–10 minutes (carryover will raise internal temp a few degrees).

Slice and Serve

Slice the rested pork into 1/2-inch medallions on a slight diagonal. Serve immediately with pan sauce (below) or your preferred side.

Pan Sauce (optional)

Prepare Pan

After removing the pork to rest, place the skillet back on medium heat. If there is excessive fat, spoon off all but about 1 tbs. Add the butter and let it melt, scraping up browned bits from the pan with a wooden spoon.

Sauté Shallot

Add the finely chopped shallot to the pan and sauté for 1–2 minutes until softened and translucent but not browned.

Deglaze

Pour the white wine (or 1 tbs additional stock) into the pan and stir, scraping browned bits from the bottom. Let it reduce by about half (about 1–2 minutes).

Simmer Sauce

Add the chicken stock, thyme or rosemary sprig, and honey. Bring to a gentle simmer and reduce until slightly thickened, about 4–6 minutes. Taste and season with 1/4 tsp salt and 1/4 tsp pepper as needed.

Finish

Remove the herb sprig. Off heat, swirl in any remaining 1 tbs butter if desired for sheen and richness. Spoon the sauce over the sliced pork medallions and serve.