This may look like a winter scene, with snow covering the floor of those polygon-shaped mud pans. But that white stuff is salt, which is plentiful here in the Badwater Basin of Death Valley National Park - which has the lowest elevation in all of North America, reaching -282 ft below sea level. The "mud" was all dried up and that and the large salt crystals made it loudly crunchy to walk on.
Those polygons are typically 4 or 5 feet wide, to give you a sense of the scale here. Further toward the Panamint mountains in the background the mud disappears and it's pure white salt, but still with the polygonal pans. This was my first visit to Death Valley, and the sunset here at Badwater Basin did not disappoint.