A Flaming Galah is Australian slang for someone who is a bit doofus, a bit of a fool, a bit of a mentalist but nonetheless is a very loveable creature.
A Flaming Galah is a person who makes a fool of themselves but isn't afraid to laugh at themselves when everyone else starts laughing at them.
"Davo mate, you poured friggin' sugar instead of salt all over your burger."
"I'm gonna eat it anyway."
"Struth mate, you're a Flaming Galah."