Horse Dung Fungus, Pisolithus tinctorius
This is Horse Dung Fungus, Pisolithus tinctorius.
Collected by Steve Deaver, 12 September 2016, in Twain Harte, Tuolumne County, growing out of a crack in a shaded area of driveway.
Images below include cross sections.
Thanks to Matthew J. L. Kilger of https://www.facebook.com/groups/MushroomIdentification/ for the identification.
Click to enlarge.