when you are making a chocalate shake for your friends; you add milk, chocolate ice cream and then you add a nice footlong turd. And to top it all off you put some whip cream and a nice little cum shot on top.
bryan: Kelsey im makin you a shitshake!
kelsey: cool i'll give it to Amber!
Any truly disgusting drink from Starbucks.
E.g. "Vanilla" Frappuccino.
Actually it doesn't have to be from Starbucks, just some high end coffee place.
Katie: Where's all your money gone!?
Amy: I know! I spent like $5.50 on some shitshake from Starbucks...