A man at a french restaraunt is outraged to find a fly in his soup, and calls for the his waiter.
The waiter comes over and inspects the soup: he sticks a finger in the soup, nods to himself, and goes back into the kitchen; he comes back with a frog, drops it into the soup, and goes back to what he was doing.
this didn't come out as "bad" (or well, depending on how you look at it) as I would have liked. other endings I was playing with were the waiter handing him a flyswatter and telling him that any more than the "sampler" was self-serve... or the waiter simply swatting the fly-in-soup with the flyswatter and breaking the whole assembly making a huge mess, or...
I'm not good with jokes. I probably shouldn't have tried. The previous one just "came to me".