I've been looking at this recently
The thing is, I don't really want anything external to the app, one generally uses Kindle on either a dedicated Kindle device or another tablet, not on a laptop or a desktop, and one expects it to be all within the app
My impression is that Amazon expect you to use Kindle books like cheap airport paperbacks, buy them read them, put them away until you run out of new reading, that's certainly how they sell you books
You can't even sort within a Collection as far as I can see, which is pretty rubbish
i think all we can do is keep complaining to Amazon
The dream obviously would be to be able to search your recipes in EYB then open the one you choose directly in a linked Kindle app on the same device, but I suspect this would be near impossible