1. Cut pork crosswise into 12 (1-inch-thick) pieces. Sprinkle both sides of pork with salt and pepper. Heat oil in a large nonstick skillet over medium-high heat. Add pork to pan; cook 4 minutes on each side or until done. Remove pork from pan; keep warm.
2. Add juice, cherries, wine, and vinegar to pan; bring to a boil. Reduce heat to medium; cook 2 minutes. Combine cornstarch and 1 teaspoon water in a small bowl. Add cornstarch mixture to pan; bring to a boil. Cook 1 minute, stirring constantly. Remove pan from heat. Add butter, stirring until butter melts. Return pork to pan, turning to coat.