Green’s Dictionary of Slang

crispie n.

In exclamations

give them a crispie! [a type of biscuit]

(N.Z.) an excl. meaning that someone has done well, and should be rewarded.

[NZ]McGill Reed Dict. of N.Z. Sl. 87: give her/him a crispie! Reward someone, from the plain wine-style biscuit studded with sugar.