Add the vinegar to a small saucepan and bring to a boil over medium heat. Continue to boil the vinegar until reduced to approximately 1/3 of a cup. The vinegar should be syrupy at this point.

Allow the reduction to cool to room temperature. Transfer to an airtight container and store until ready to use.

Thread one strawberry onto a wooden skewer, followed by one basil leave folded in half, one mozzarella ball, a second basil leaf and one strawberry. Set aside and repeat with remaining ingredients.

Drizzle the balsamic reduction over the skewers.

Serve immediately.