Cut rolls in half lengthwise. Cut sauce to desired thickness and add slices to open rolls (or to half of the Italian bread slices). Mix together the mayonnaise and chipotle in a small bowl until well mixed. For each sandwich, spread cut surfaces of roll with the mayonnaise mixture. Place 1/4 cup spinach, an onion slice, 4 ounces of turkey and a slice of cheese on bottom half of roll. Place top of roll on sandwich and flatten. Brush both sides of sandwiches with olive oil. Heat sandwiches in panini press according to manufacturer's directions. Or heat sandwiches in a large skillet over medium heat. Place a heavy pan on sandwich and cook 10 minutes, turning once or until sandwich is toasted and hot throughout. Makes 6 sandwiches.