Any situation in which a person recieves an item that they didn't want, but are forced to deal with. There are several varieties.
It originated from members of SWBGS dropping expensive and/or unwanted items onto unsuspecting victims shopping at supermarket checkouts.
ATM basting: When someone is withdrawing cash from an ATM, pressing the £200 button.
Supermarket basting: When someone leaves an inappropriate item on someones shopping at a supermarket checkout.
Eg, "You wanna baste that guy with these scottish biscuits?"