When you try to cook raw fish fillets the icon changes to the cooked state of the item but the name and description stays the same. I tried this by both cooking in a copoking pot with water above a gas stove and on a stick over an open fire. The icons change accordingly to boiled and baked fish but the names and descriptions for the items are still raw fish fillets. I have not tried to eat them to test if they actually are raw because I would rather my character not get sick. I didn't try for too long but the fillets also never seemed to burn, I left them on for 3-5 minutes after the icon changed thinking it was a two step thing but they never burned or changed.