Im trying to find out who do i respectivly ask what to do about buying dirty food...?

im a trucker and i was ping tru Glendale Ky. stoped at the PILOT truck stop,@ exit-86: on I65 bought me ah fish meal with a large fry no salt got my food to go i ate the fry,s and about to put ketchup on my fish sandwich ! wowww as i looked at the top bread i noticed that there was (DIRT) on the bread i have the sandwich just bought it today, i would like to sue these people for selling me dirty food delibretly,, they knew the bread was dirty it was quite obvious some one help me to the proper complaint dept i have the sandwich as evidence....a_town566@yahoo.com