1. Combine sliced mango, syrup, and remaining ingredients in a medium saucepan over medium-high heat; bring to a boil. Reduce heat; simmer 5 minutes, stirring occasionally until mixture is thickened and mango is very tender. Cool slightly.
2. Pour mixture into a blender, and process until smooth. Pour into an 8-inch baking dish; cover and freeze 3 hours or until firm.
3. Scrape mango mixture with a fork; divide among 4 serving dishes. Serve immediately.