I spoke to Lenaid from Sims 4 Studio about how to edit the items the sims cook with and he wrote out a tutorial for me!
I'm popping it here as I'm not sure when I'll have a chance to properly look at this (probably this week but tis busy!)
So in case you lot would like to try it before I make the video you can!
I've attached it to this post as it's rather lengthy x