If everything tastes like chicken, what does chicken taste like?!
If everything tastes like chicken, what does chicken taste like?
Answers:
Itself.
Note that all those other things only taste "like" chicken, not identical to it. The same way that we'd call other colors "blueish" but just call blue, blue. Chicken is a more familiar taste than brains or gluten meat or whatever else is said to taste "like chicken", thus it's the reference point.