Preparation Place pork and vinaigrette in pie dish; turn to coat. Let stand 10 minutes. Melt butter in heavy medium skillet over medium heat. Using tongs, lift pork from marinade; shake off excess. Transfer pork to skillet, reserving marinade in dish. Sprinkle pork with pepper. Sauté until brown, about 3 minutes per side. Transfer pork to plate. Add shallot to skillet; stir until softened, about 1 minute. Add broth, cherries and reserved marinade; bring to boil, scraping up browned bits. Return pork to skillet. Simmer until pork is cooked through, cherries are tender and sauce is slightly reduced, about 2 minutes per side. Season with salt and pepper. Transfer pork to plates; top with sauce.