I love to make mushroom risotto

Dried mushroom powder can be gritty.
Reconstitute to get a nice dark liquid, then filter the grit out.

I LOVE using dried, ground mushrooms in rubs. I just blitz it in a coffee grinder with other spices like coriander, black mustard, pepper, etc. and rub it on beef and pork. I think it works better with heartier meats, but I've never tried it on chicken/fish. It's also really amazing in braises/stews. It's like concentrated mushroom power.

Adding to Le Bec Fin's suggestion I would use the water you reconstitute the mushrooms into the risotto for added flavor.

Like whole dried mushrooms, i am guessing the powder needs some warm liquid to bring out its flavor- before it is added to dishes? Then it could be added to anything you like shiitakes for: soups, sauces, stir fries, risotto. I have read of chefs who coat fish filets w/ it before sauteeing......