Green’s Dictionary of Slang

a general term of approbation, easy, privileged, wonderful, perfect.

1917		G. Bowerman diary 6 Oct. in Carnes Compensations of War (1983) 27: It wasn’t exactly a ‘gravy’ job.
1938		D. Runyon ‘The Big Umbrella’ in Runyon on Broadway (1954) 555: It is a left jab followed through fast with a right cross, and it is considered quite a gravy punch if properly put on.
1957		R. Prather Always Leave ’Em Dying 137: That made the going easier for me, but it wasn’t all gravy.
1975		G. Underwood ‘Razorback Sl.’ in AS L:1/2 59: That chick is gravy.
1981		E. Bunker Little Boy Blue (1995) 79: It ain’t always gonna be gravy [...] Believe me, boy.
1987		Eble Campus Sl. Oct. 3: gravy – easy.
1997–2001		Online Sl. Dict. 🌐 gravy adj 1. very good, excellent; COOL. [...] 2. easy. (‘Man, that climb was gravy’.). [Ibid.] gravy noodles adj 1. very good, excellent; COOL.
1999		Indep. Rev. 14 Aug. 5: It’s all gravy. Every single thing I accomplish. It’s gravy. It’s like I already won.
2014		C. Eble (ed.) UNC-CH Campus Sl. Spring 2014 7: GRAVY NOODLES — excellent.