Amanita smithiana

Characteristic: when touched it has a flaky, chalk like texture
The gills are adnate, closely spaced, with a faint decurrent line on stem apex.
The spore print was white. No veil.

Poisonous - Deadly - sometimes mistaken for matsutake mushroom -

It is responsible for poisonings in the Pacific Northwest when mistaken for the edible and sought after Tricholoma magnivelare. It causes initial gastrointestinal symptoms that manifest 1 to 12 hours after eating the mushrooms, followed by acute renal failure after a delay of 2–6 days. This is often severe, requiring hemodialysis, but most patients recover normal kidney function within several weeks
From Wikipedia

Note: These usually taste good; therefore the person consuming them does not think they are the wrong mushrooms.

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