Chestnut mushrooms (Pholiota adiposa) are a newcomer on the cultivated mushroom scene. I took a week and cooked my way through a bunch recently. The best thing I made was a simple salad that shows off their delicious, chewy texture.
Background on their use as a traditional food is scarce, but they're one of at least two or three species of Pholiota cultivated in Japan, along with Pholiota nameko. Both are fantastic mushrooms for soup.
These can be hard to find and not a lot of growers carry them, so you're best bet to get your own is probably a grow block from North Spore, which is where I got mine.
If you're in the Twin Cities, R and R cultivation can sell them in bulk.
Chestnut mushroom salad
https://foragerchef.com/chestnut-mushroom/
Pickled mushrooms mentioned in the video
https://foragerchef.com/fresh-wild-mushroom-conserve/
North Spore
https://northspore.com/products/grow-your-own-chestnut-mushrooms?_pos=8&_sid=cb10af15b&_ss=r