Place a medium saucepan over medium heat, add water, sugar, lemon peel, and mint, bring to a steady boil.

Stir constantly until sugar is completely dissolved.

Remove from heat and stir in lemon juice and vanilla.

Let mixture cool completely, for about 20-30 minutes.

Once cooled, discard the mint and the lemon peel.

Add mango to a food processor and puree until smooth.

Add pureed mango to a pitcher and add the syrup mixture, stir to combine.

Refrigerate for at least 2 hours before serving.

Add ice to tall glasses, fill 1/3 of the way with chilled mango lemonade, then add club soda, stir to combine.

Garnish glasses with lemon slices and serve.