Spread pesto: Evenly spread the basil pesto over one side of each slice of ciabatta bread.
Layer ingredients: Layer the fresh mozzarella slices over the pesto on one slice of the ciabatta. Follow with the tomato slices and fresh basil leaves.
Season: Sprinkle a pinch of salt and pepper over the top of the ingredients.
Assemble sandwich: Place the other slice of ciabatta, pesto-side down, on top of the assembled ingredients.
Optional drizzle: Drizzle a small amount of olive oil over the top of the sandwich if desired.
Serve: Cut in half and enjoy your delicious Caprese Sandwich with Pesto!