What a fabulous problem to have @Harters! My best suggestions would be to sauté and freeze like others have suggested. Sometimes I also add onions, and then garlic at the end so they’re ready to go in a variety of things.
OR, I would make the base for mushroom soup. The 2 recipes I like are the old Moosewood Cookbook recipe for Hungarian Mushroom Soup, or Anthony Bourdain’s famous mushroom soup. Just don’t add the dairy, until it’s thawed, warmed, etc or whatever the recipe says. Both easily found on the internet. Haven’t tasted chestnut shrooms, unless they go by a different name in the US.
