Meanings
Probably a humorous antonym of bad egg (“someone whose behaviour is reprehensible or irresponsible; a rogue”).[1]
How to pronounce "good egg":
AU
A good person, someone to be trusted; a friend.
Example Sentences
1
She's always willing to help out, she's a real good egg.
2
I can count on him to be reliable, he's a good egg.
3
Even in difficult situations, she remains calm and collected, truly a good egg.
4
He's a good egg; he always puts others first.
5
She never complains and is always cheerful, a true good egg.