In a small saucepan, combine the water, sugar, chopped basil leaves and lemon zest. Bring to a boil and reduce to a simmer over medium heat, stirring constantly until the sugar dissolves and the mixture slightly thickens, 3-4 minutes. Remove from heat.

Puree the strawberries using a blender or food processor until smooth. Add the lemon juice and balsamic vinegar and pulse to combine. Pour in the slightly cooled syrup and pulse again just until well-combined.

Pour the mixture into an 8×8 baking dish. Cover lightly with plastic wrap and place in the freezer. Freeze for 60 minutes, and then gently scrape the top layer with a fork. Replace the plastic wrap and freeze another 30 minutes, and re-scrape the top layer with a fork. Repeat 2-3 more times until it is frozen through. Divide into four serving glasses and garnish with additional fruit and basil.

Note:
I have made these with and without adding alcohol. Honestly, I liked them much better without but to make them a little boozy, add 1 1/2 tablespoons of rum or vodka (or your choice of liquor) in with the lemon juice and balsamic vinegar.