In a medium saucepan, combine 1 cup of granulated sugar, 8 ounces of water, and a handful of fresh basil leaves. Heat over medium heat, stirring gently until the sugar has completely dissolved, about 3-4 minutes. Lightly muddle the basil leaves and let the mixture simmer for 1 minute.

Remove the simple syrup from heat and allow it to steep at room temperature for about 15-20 minutes until fragrant.

In a large pitcher, mix together 40 ounces of cold water with 8 ounces of freshly squeezed lemon juice. Stir well until combined.

Strain the cooled simple syrup into the pitcher with the lemonade mixture and discard the basil leaves. Stir gently and adjust sweetness if needed.

Refrigerate the Basil Lemonade for 1-2 hours. Serve over ice and garnish with a basil leaf or lemon slice.