Fish Fillet is an item obtained by cooking certain types of fish.
Note: This item replaces Cooked Cod in regular gameplay, meaning all functionality of Cooked Cod exists for Fish Fillet, too.
Fish Fillet can be obtained by cooking Cod, or some types of Custom Fish, with a Furnace, Smoker, Campfire, or Soul Campfire.
It can also be obtained any way the default Minecraft item "Cooked Cod" can be obtained (killing a Cod with Fire Aspect, in a Buried Treasure Chest, etc).
Fish Fillet is a food item, that can be consumed at a normal rate. It can only be eaten if the player is hungry. Fish Fillet provides 5 nutrition (hunger points) and 6 saturation.
This item also has the same uses as the default Minecraft item "Cooked Cod," including the ability to be fed to Wolves.
Carrots give 3 nutrition and 3.6 saturation
Bread gives 5 nutrition and 6 saturation
Steak gives 8 nutrition and 12.8 saturation