That's what my 4 yr. old calls marshmallows. Every morning for breakfast she requests "Mushroom cereal." I know she's referring to 'Lucky Charms' others don't.
My husband for example. The first time our little Diva in-training asked him for some "mushrooms" he looked puzzled.
"You want some mushrooms?" he asked.
"Yeah Daddy I yike mushrooms. Der yummy!" Diva tells him.
*Insert 30 second pause*
"Okay.........you really want mushrooms??" Clearly clueless.
"Stac...(now whispering so the Diva doesn't hear) What are "mushrooms"?"
"Marshmallows. She wants 'Lucky Charms.'"
And so Daddy fixed Diva her bowl of "mushrooms" and all was right with the world.