Boil water and brown sugar in a small saucepan over low heat until the sugar dissolves. Let it boil for 5 minutes. Pour into a bowl and allow to cool to room temperature. 

Mix the mango pulp and the lemon juice in the brown sugar syrup. Strain. 

Transfer to the ice cream machine and process according to the manufacturer’s instructions.   

Transfer to an airtight container.  

Freeze at least 2 hours before serving.  

Use fresh mint leaves to decorate.