If you're into historical recipes, I can't recommend the "Tasting History" channel on youtube enough. It intersperses replicating the recipes with a whole load of historical context and nuance. "The Forme of Cury" has made some appearances on it as well.
Also highly recommended - the British Food History Podcast (and companion blog), with the aptly named Dr. Neil Buttery. Here's the episode about Forme of Cury.
There is a (disputed) story that curry was used as a dismissive way to refer to Indian food ("just cooking"), which then became used to refer to Indian food.
Could this be where "to curry favor" comes from? Where curry, in it's "to cook" form basically means "to make"? So like "to cook up some favor" as "to generate favor"