I'm trying to use the RegisterOvenRecipe imc but I've been at it for hours now and I can't seem to get the correct values in for ItemStack, how is this supposed to be formatted/could I get an example?

Send an IMC message with id RegisterOvenRecipe to cookingforblockheads, the message being of type NBTTagCompound.

Inside the NBT, there should be another compound Input and one Output. Those are used to create ItemStacks, meaning they must be in the ItemStack format ItemStack.writeToNBT(...)

In JSON it would look something like

{
    "Input": {
        "id": "minecraft:raw_fish",
        "Count": 1,
        "Damage": 0
    },
    "Output": {
        "id": "minecraft:cooked_fish",
        "Count": 1,
        "Damage": 0
    }
}```

Thank you for the response, works a treat 😄