In a pot add balsamic vinegar and sugar. Bring to a boil stirring frequently until the sugar has dissolved. Then reduce the heat and simmer until the mixture has thickened (about 10 minutes). As soon as it's reduced by half transfer to a glass storage container. Let cool to room temperature then place in the refrigerator until ready to serve.
Cut the vine ripe tomatoes in ¼ inch pieces horizontally (discard the stem pieces). Place the mozzarella and tomatoes alternating on a plate.
Wash basil, pat dry, and place in between the pieces of mozzarella and tomatoes. Sprinkle salt and black pepper to taste on top , drizzle extra virgin olive oil and balsamic reduction sauce over the salad.