1. Combine 1 tablespoon olive oil, rind, and juice in a large zip-top plastic bag. Add lamb to bag; turn to coat well. Let stand at room temperature for 10 minutes. Remove lamb from bag; sprinkle evenly with salt and pepper.
2. Heat a large grill pan over medium-high heat. Coat pan with cooking spray. Add lamb to pan; cook 2 minutes on each side or until desired degree of doneness.
3. Place vinegar in a small skillet over medium-high heat; bring to a boil. Cook 3 minutes or until vinegar is syrupy. Drizzle vinegar and remaining 1 teaspoon oil over lamb.