Combine the quartered strawberries, sugar, and 1 cup of water in a small saucepan. Bring to a simmer over medium heat, stirring to dissolve the sugar.

Reduce the heat to low and let it simmer for about 10 minutes, or until the strawberries have broken down and the syrup has thickened slightly. Mash the strawberries with a spoon if needed.

Remove from heat and let it steep for another 10 minutes. Strain the syrup through a fine-mesh sieve into a bowl, pressing on the solids to extract as much liquid as possible. Discard the solids. Let the syrup cool completely.

In a large pitcher, combine the cooled strawberry simple syrup, fresh lemon juice, and 4 cups of cold water.

Stir well to combine. Taste and add additional sweetener if desired, stirring until dissolved.

Serve over ice. Garnish with fresh mint sprigs, lemon slices, and fresh strawberries, if desired.