Toast the ciabatta rolls until they are golden brown and crisp.
Spread about 2 tablespoons of the pesto on the bottom half of each roll. Top with the the sun dried tomatoes and slices of mozzarella. Season the tomatoes with salt then layer them on the sandwiches.
Spread 1 tablespoon of the balsamic glaze on the top half of each of the sandwich rolls.
Close the sandwiches and cut in half. Serve immediately.