You mean the square fish-like substance pressed into a block and covered with a sticky white tartar-like sauce ?

Part of a funny review:
The sandwiches are very small; the filets could only be smaller if they had been cut from Angelina Jolie's bicep. My first thought was that I couldn't even really tell I was eating fish, the texture was similar to fish, but it didn't really resemble a fish taste at all.

McDonald's Filet-O-Fish [Review] - Fast Food Geek

:D :D :D