Put a grill pan over medium-high heat or preheat a gas or charcoal grill. Drizzle the pork chops on both sides with olive oil and season with salt and pepper, to taste. Sprinkle both sides with the herbs de Provence and grill for 10 minutes. Turn the chops over and cook until an instant-read thermometer inserted into the thickest part of the meat registers 160 degrees F. Transfer the chops to a cutting board and let them rest for 10 minutes. Slice each chop into 6 (1/4-inch thick) slices.
In a small bowl, combine the mayonnaise, basil, lemon zest, and lemon juice until smooth. Season with salt and pepper, to taste.
To assemble the sandwiches: Lay the bottom half of the bread on a work surface and spread with 1/2 of the mayonnaise mixture. Add the lettuce leaves, arrange the cheese slices on the lettuce and top with the pork slices. Spread the top half of the bread with the remaining mayonnaise mixture and cover the sandwiches. Slice the loaf into 4 pieces and serve.