Cut the ciabatta rolls in half horizontally and place them on a baking sheet, cut side up.
2 ciabatta rolls
In a medium bowl mix the mayonnaise and the pesto together until combined then spread some of the mixture on each side of the cut bread.
4 tablespoons pesto, 2 tablespoons mayonnaise
Layer the sliced turkey on one side, and the tomato, red onion, and provolone cheese on the other side of the rolls.
1/2 pound sliced deli turkey, 1 tomato, 1/4 red onion, 4 slices provolone cheese
Place the baking sheet in the oven and bake for about 8-10 minutes, or until the cheese is melted and the sandwiches are heated through. You can then broil the sandwiches for a minute of two to get the cheese perfectly toasted and golden.
Remove from the oven and top with arugula or lettuce if desired then close your sandwiches with the other halves and enjoy!