Oh cool, you're close enough to me (Washington) that I can use my local resources to get closer.
Look into Lactarius cascadensis and Lactarius cordovaensis (they may be the same thing).
Paraphrased from Danny Miller https://www.alpental.com/psms/ddd/Lactarius/index.htm
a lilac grey/cinnamon cap that is zoned. It is large, with gills the colour of the cap and a mild taste found under alder. It has watery-white latex that stains tissues pink/purple and a scrobiculate stem.
Those are supposed to be pretty rare, if you've still got it, consider drying it and seeing if anyone from a local mycology club is interested in studying it.
It's a chocolate-flavored sandwich-cookie, not a cookie version of a chocolate sandwich.