Combine water, sugar, chopped basil leaves, and lemon zest in a small saucepan.

Bring to a boil over medium heat, then reduce to a simmer.

Stir constantly until the sugar dissolves and the mixture slightly thickens (3-4 minutes).

Remove from heat and let cool slightly.

Puree the strawberries in a blender or food processor until smooth.

Add the lemon juice and balsamic vinegar to the pureed strawberries.

Pulse to combine thoroughly.

Pour in the cooled syrup and pulse again until well-combined.

Pour the mixture into an 8x8 baking dish.

Cover lightly with plastic wrap and place in the freezer.

Freeze for 60 minutes, then gently scrape the top layer with a fork.

Replace the plastic wrap and freeze for another 30 minutes.

Re-scrape the top layer with a fork.

Repeat the freezing and scraping process 2-3 more times until the mixture is frozen through.

Divide the granita into four serving glasses.

Garnish with additional fruit and basil, if desired.