01 - Combine water and sugar in a small saucepan. Bring to a gentle boil over medium heat, stirring constantly until sugar completely dissolves, approximately 2–3 minutes.
02 - Remove syrup from heat and stir in fresh mint leaves. Allow mixture to steep for 10 minutes to extract mint flavor into the syrup base.
03 - Pour mixture through a fine mesh strainer to remove mint leaves. Let strained syrup cool completely to room temperature before proceeding.
04 - In a mixing bowl, whisk together cooled mint-infused syrup, fresh lemon juice, and grated lemon zest until fully incorporated.
05 - Transfer mixture to an ice cream maker and churn according to manufacturer's instructions for 20–25 minutes until mixture reaches thick, slushy consistency.
06 - Spoon churned sorbet into a freezer-safe container. Cover tightly and freeze for minimum 4 hours or until firm enough to scoop.
07 - Scoop sorbet into chilled bowls or dessert glasses. Decorate with fresh lemon slices and mint sprigs if desired. Serve immediately while firm.