01 - Combine sugar and water in a small saucepan. Heat over medium heat, stirring continuously until sugar completely dissolves. Remove from heat and allow syrup to cool to room temperature.
02 - Place raspberries, cooled syrup, lemon juice, and chopped mint leaves in a blender. Process on high speed until completely smooth and uniform in texture.
03 - Pour blended mixture through a fine-mesh sieve into a clean bowl. Use a spatula to press puree through, extracting as much liquid as possible while removing raspberry seeds.
04 - Transfer strained mixture to ice cream maker and churn according to manufacturer instructions for 20-25 minutes until mixture reaches thick, creamy consistency. Alternatively, pour into shallow dish and freeze for 1 hour, then stir vigorously with fork. Repeat every 30 minutes until set, approximately 3-4 hours total.
05 - Spoon churned sorbet into freezer-safe container. Cover tightly and freeze for minimum 2 hours until firm enough to scoop.
06 - Scoop sorbet into chilled bowls or cones. Decorate with fresh mint leaves and whole raspberries if desired.