My mother and I are reading a book in which someone was murdered by poisoned candy. Now that's just mean.
How many murder stories have you read in which the poison was stirred into something the victim drank, slipped into a condiment only the victim used--or a random victim would use, put into something the victim ate or a medicine the victim took? That's not even counting Mickey Finns (anybody else know what a Mickey Finn is?). There's something particularly evil about turning something that should be nourishing--or at least pleasant--and turning it into something deadly, something very Trojan Horse-y about watching your victim administer his/her own murder weapon.
You can even set the trap and be somewhere else with an iron-clad alibi when the deed comes to fruition.
But what if your intended victim doesn't feel hungry/thirsty and somebody else is killed by mistake? So many books and stories in which the detective or police run ragged looking for Mr. A's murderer, only to finally discover that the intended victim was Miss B and they have to start all over again. It makes for a nice confusion (if you're a reader or writer, not if you're a detective or investigating officer--or, come to that, if you're a victim).
And this is quite beside the murderous possibilities of just plain bad cooking....