Wash the strawberries thoroughly under running water.
Hull the strawberries and slice them into halves or quarters.
In a blender, combine the sliced strawberries with half a cup of water and blend until smooth.
In a large pitcher, combine the freshly squeezed lemon juice and sugar, stirring until the sugar is dissolved.
Add the strawberry puree to the pitcher and mix well.
Pour in the remaining cold water and stir to combine.
Adjust sweetness by adding more sugar or water if desired.
Serve over ice and garnish with fresh mint leaves and strawberry slices.