why when u cook fish does it cook in layers??

Answer 1

When you cook fish, or any food, it cooks from the outside in. Heat is exposed to the exterior, but the center can remain cool, until enough heat is transferred from the outer portion of the food. This can give the appearance of cooking in layers.

Answer 2

Not all fish cooks the same. some fish is "flakey" which would make it look as if its cooked in layers.
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