Does anyone know where I can buy these mushrooms in Chiang Rai?

They look like and taste a bit like beef.
In Chiang Mai, I have seen them for sale in some vegetarian restaurants.

Thank You

This translates as shitake mushrooms - het hom bprung. Better to buy them fresh though, and not to store in plastic at all.

Shiitake Mushrooms, of course... they taste like Beef, they are grown in Cow Patts.