Cooking The Books
Meaning
This phrase is mostly used by tax lawyers when they want to convey a message that the account books are tempered so as to avoid tax payment.
Origin
The first use though in a different format was in 1636 by Earl of Strafford in his Letters:
“The Proof was once clear, however they have cook’d it since.”
Tobias Smollett’s The Adventures of Peregrine Pickle in 1751 used this phrase in its real sense:
“Some falsified printed accounts, artfully cooked up, on purpose to mislead and deceive.”