Final answer:
The crunch in the original BBQ chicken sandwich comes from various components of the sandwich, such as the bread, toppings, and chicken preparation.
Step-by-step explanation:
The crunch in the original BBQ chicken sandwich comes from various components of the sandwich. One key element is the bread used. Perhaps a ciabatta roll or a crusty baguette is used, both of which have a crispy texture. Another factor contributing to the crunch is the use of toppings like lettuce and pickles. These vegetables add a fresh and crisp element to the sandwich. Lastly, the chicken itself can be breaded and fried, which adds a crunchy texture to the sandwich.