Green’s Dictionary of Slang

1. money; thus have the gingerbread, to be rich; as adj., showy, ostentatious.

c.1617		Fletcher Chances I vi: Without commission: Why, it would never grieve me, If I had got this Ginger-bread.
1682		Buckingham Chances I vi: [as cit. c.1617].
c.1698		B.E. Dict. Canting Crew n.p.: Gingerbread Money.
1724		Hist. of the Remarkable Life of John Sheppard 49: He said, They were all Ginger-bread Fellows, and came rather out of Curiosity, than Charity.
1737, 1759, 1760, 1776		Bailey Universal Etym. Eng. Dict. [as cit. c.1698].
1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue.
1811		Lex. Balatronicum.
1834		(con. 1737–9) W.H. Ainsworth Rookwood (1857) 187: Your old dad, Sir Piers (God help him!), had the gingerbread, that I know.
1864		London Standard 13 Dec. 3/2: We do not find... the word gingerbread used for money, as we have heard it both before and within the last six months .
1976		E. Dahlberg Olive of Minerva 119: Imagine a gawk like Abel with a light-heeled jill who’s looking for easy gingerbread.

2. see ginger-cake under ginger adj.