Prep Time: 10 minutes
Cook Time: 10 minutes
Total Time: 20 minutes
Servings: 4
Heat chopped strawberries, water, sugar, honey, and basil leaves in a saucepan over high to a boil. Reduce heat to medium-low and simmer strawberry syrup until sugar dissolves and strawberries break down, 10 minutes. Crush strawberries with a potato masher and cool to room temperature; discard basil leaves. Transfer strawberry syrup into a large measuring cup and chill until ready to serve.
Stir lemon juice into strawberry syrup. Divide strawberry syrup among glasses; stir to blend. Fill glasses with ice and top glasses off with tonic water. Stir to blend. Garnish drinks with basil sprigs, lemon slices, and strawberries, and serve immediately.