Creating the Chicken Pesto Sandwich with Mozzarella is easy if you follow these simple steps:

1. Preheat Grill or Pan: Heat your grill or a non-stick skillet over medium-high heat.
2. Season Chicken: Season the chicken breasts with salt, pepper, and a drizzle of olive oil.
3. Cook Chicken: Place the chicken on the grill or skillet and cook for about 6-7 minutes on each side, or until the internal temperature reaches 165°F (75°C). Remove from heat and rest.
4. Slice Chicken: Once rested, slice the chicken breasts into thin strips.
5. Prepare Bread: Slice the ciabatta rolls or baguette in half horizontally.
6. Spread Pesto: Generously spread basil pesto on both halves of the bread.
7. Add Chicken: Layer the sliced chicken evenly on the bottom halves of the bread.
8. Add Mozzarella: Top the chicken with slices of fresh mozzarella.
9. Broil or Grill the Sandwich: If desired, place the assembled sandwich under a broiler for 2-3 minutes until the cheese melts, or grill for an additional 2-3 minutes.
10. Add Greens: If using, add a layer of arugula or spinach on top of the melted mozzarella.
11. Close and Serve: Place the top half of the bread onto the sandwich, slice, and serve immediately.