A doctor goes to the same bar every day and orders an Almond Daiquiri.
He gets to be so regular, showing up at the same time every day, that the bartender knows to make the drink and has it waiting for the doc when he arrives.
One day the bartender goes to make it and realizes he doesn’t have any almonds.
He does, however, have some hickory nuts.
So he mashes them up and whips them into a daiquiri, assuming the doctor won’t know the difference.
The doctor comes in and is presented with the drink.
He takes a sip and immediately notices something is up.
“Is this an almond daiquiri?” he asks.
“No,” says the bartender, “it’s a hickory daiquiri, doc.”