Heat 2 tablespoons peanut oil in a large, ovenproof skillet, over moderate heat.

Season pork tenderloin with salt and pepper and sear in the skillet until each side is nice and golden brown. You’ll know when the meat is ready to be turned when it no longer sticks to the pan.

Once each side is seared, transfer the pan to the oven and roast until the internal temperature reaches 145°F, about 15-20 minutes. Remove pork to a carving board and let it rest for 10 minutes while you make the sauce.

Place the skillet back on the stovetop over moderate heat. Add the shallot and garlic and sautée until soft. If there isn’t much oil left in the pan, add another tablespoon. Add the flour, stirring with a wooden spoon, letting it cook for about 2 minutes.

Meanwhile, in a medium bowl, whisk together chicken stock, mustard, vinegar, and maple syrup.

Pour about ⅓ of the mixture into the skillet, whisking as you add it. Once it is starting to bubble, add half of what’s left, whisking as you go, let it come up to a bubble, and then repeat with the remaining liquid. Stir and let it reduce to your desired consistency. Season to taste with kosher salt and freshly cracked black pepper.

To serve, slice the pork into medallions and serve with the sauce alongside.