Green’s Dictionary of Slang

1. a black person [coon n. (4)].

1992		R. Puxley Cockney Rabbit.
1999		Bug (Aus.) 1 Nov. 🌐 Mundine’s problem which prevents him making the Australian side is not that he is an egg and spoon, but that he is an uppity coon.

2. (Aus.) a fool, a silly person [goon n.¹ (1)].

2002

Pete’s Aussie Sl. Home Page 🌐 egg and spoon: a goon, a silly person .

3. (Aus.) a pimp [hoon n. (1)].

1975		Bulletin (Sydney) 26 Apr. 46: Rhyming slang did filter through into the idiom. but the knock-abouts quickly turned most of the phrases into shortened versions – [...] comics (short for comic cuts; guts or belly); egg (short for egg and spoon: hoon, or prostitute’s pimp); onka (short for Onkaparinga: linger).
1990		Tupper & Wortley Aus. Prison Sl. Gloss. 🌐 Egg and spoon. Rhyming slang for hoon, ie a pimp. Sometimes just egg.
1999		G. Seal Lingo 91: An egg and spoon is a hoon.