Prepare the roasted bell peppers and set them to the side.
Next, prepare the chicken cutlets and keep them warm.
Add the oil to a large frying pan over medium-high heat and cook until it smokes lightly.
Place the sliced broccoli rabe or broccolini and sauté for 3 to 4 minutes or until tender. You may need to adjust the heat if it is getting too hot.
Next, stir in the garlic and cook for 30 to 45 seconds while constantly stirring until it becomes fragrant. Remove the pan from the heat and set it to the side.
Place the chicken cutlets on a sheet tray, slightly layered over each other, and generously and evenly spread the shredded cheese.
Add them to a center rack in a pre-heated oven with the broiler on high. Broil for 2 to 4 minutes or until the cheese is melted and lightly browned.
Spread the pesto on the bottom of the loaf of ciabatta and then add on the prosciutto slices.
Place the cheesy chicken on top of the prosciutto.
Layer with the cooked broccoli, roasted bell peppers, and optional balsamic reduction.
Place on the top slice of bread, slice and serve.
Notes
Make-Ahead: These are meant to be eaten as soon as they’re done being assembled. However, you can keep them over a rack on a sheet tray and in the oven at low temperatures (<200°) for up to 30 minutes.How to Store: The sandwich can be stored covered in the refrigerator for up to 3 days. It will not freeze well.How to Reheat: Wrap the sandwiches in foil, place them directly on a middle rack in the oven, and bake at 350° for 10 to 15 minutes or until warmed.This sandwich is also delicious eaten cold.Replace the peppers with oven-roasted tomatoes.