I think this is The Chicken of The Woods fungus.
I found it growing at Rialto Beach. It was huge, I didn't know what it was, looks like it is edible, if I have id'd it correctly. Beautiful color and size, it was growing on a washed up log.
"Laetiporus sulphureus: The Chicken of the Woods
[ Basidiomycetes > Polyporales > Polyporaceae > Laetiporus . . . ]
"The "Chicken of the Woods" is a popular edible, and easily recognized by its color, soft texture, and absence of gills. I'm not a big fan (it's a little "fungus-y" for me), but I know many people who love it. The young rosettes and the tender edges from mature clusters are more palatable than the older, tougher specimens. Though the Chicken of the Woods is a safe and easily recognized edible mushroom, it should not be eaten raw; there are reports of people being adversely affected when the mushroom was not cooked.
Recent mycological "splitting" has resulted in an array of species spanning North America, nearly all of which formerly "passed" as Laetiporus sulphureus. See the comments below for some of the details.
Description:
Ecology: Parasitic and saprobic; growing alone or, more typically, in large clusters on decaying logs and stumps of hardwoods and conifers; summer and fall, rarely in winter and spring; widely distributed as a species cluster, but the "true" Laetiporus sulphureus may be limited to areas east of the Rocky Mountains (see below). Laetiporus sulphurues causes a reddish brown cubical heart rot, with thin areas of white mycelium visible in the cracks of the wood. The mushrooms do not appear until well after the fungus has attacked the tree; by the time the chickens appear, they are definitely coming home to roost, as far as the tree's health is concerned.
Fruiting Body: 5-60 cm broad, up to 4 cm thick; fan-shaped to obtusely semicircular; smooth to gently wrinkled; suedelike; bright yellow to bright orange when young, frequently fading in maturity and with direct sunlight."
Mushroomexpert. com