Pork Tenderloin with Roasted Plums and Rosemary

To roast plums: Preheat oven to 400°F. Place plums and 2 rosemary sprigs in an 8-inch-square baking dish. Whisk water, vinegar, 4 tablespoons sugar and peppercorns in a small bowl until the sugar dissolves. Scrape seeds from vanilla bean; add the seeds and bean to the vinegar mixture. Pour the mixture over the plums. Sprinkle with the remaining 2 tablespoons sugar.

Roast the plums, uncovered, until tender and beginning to break down, 20 to 25 minutes. Discard the rosemary and the vanilla bean. Transfer the plums to a serving platter and cover with foil. Strain the roasting liquid into a small saucepan and bring to a boil. Reduce heat to medium-high; cook until reduced to 1/2 cup, 6 to 8 minutes. Pour the sauce over the plums; keep warm.

To prepare pork: Meanwhile, heat oil in a large ovenproof skillet over medium-high heat. Sprinkle pork with pepper and salt. Add to the skillet and brown on all sides, 5 to 8 minutes.

Transfer the pan to the oven; bake at 400°F until an instant-read thermometer registers 155 and 176°F and the pork has just a hint of pink in the center, 10 to 15 minutes. Transfer the pork to a cutting board and let rest for 10 minutes. (The internal temperature will increase to 160 and 176°F during resting.) Cut the pork into thin slices and serve with the roasted plums.