Crusty toast is a sexual act performed by 2 people of same of different sex during intercourse. the first person has to shit all over the second person's chest, let it dry for 2 days while the second person feeds on his own shit and the butt juice from the shit drying on his chest. after the shit dries it has to be scraped off with a knife and put on a toast. voila! now both of them can enjoy a crusty toast on a pleasent wednesday morning!
"Dude, Mike and Molly had a smelly crusty toast this morning!"