Scrape seeds from bean. Combine seeds, bean, and milk in a saucepan. Bring to a boil; remove from heat, and let stand for 30 minutes. Discard bean. Add sugar, gelatin and salt. Let stand 1 minute. Cook over lo heat 5 minutes or until gelatin disolves, stirring occasionally. Cool completely. Stir in yogurt and corn syrup. Pour into a bowl; cover and chil 8 hours. Pour into a freezer can of a 1-quart hand-turned or 1/2-gallon electric freezer. Freeze according to manufacturer's instructions. Allow to ripen 1 hour in freezing can. Garnish with mint, if desired. Yield: 8= servings