This was at a park, a kid stepped in it unfortunately. I'd never seen the dog vomit fungus before in real life!
Two large white masses at the top of a dead Monterey pine tree in an open space at the top of Valley Steps which match the descriptions of Enteridium lycoperdon. This morning, one had burst and showed they cocoa powder-like insides mostly blown away leaving the spore print. Another large mass had formed below the first two. The sizes were about 8-10 inches square.
For more than a year, I have noticed small buttons of similar masses scattered over the trunk.
A common slime mold that grows on dead logs.