Cut the tomatoes in half.
Cut the Cache Valley string cheese in 1/2 inch bites.
Slide a piece of cheese onto a toothpick. Next add a basil leaf, you may need to fold the larger leaves in half. Slide a tomato half onto the bottom with the cut side down (this will help your skewers stand up straight.)
Meanwhile, add balsamic vinegar to a small sauce pan and place over high heat. Bring to a boil, reduce heat to low and simmer for 10-15 minutes to reduce.
Allow reduced balsamic vinegar to cool and then lightly drizzle over skewers and arrange skewers on a platter for serving.