Green’s Dictionary of Slang

rasher of bacon n.

a fiery drink.

1756

W. Toldervy Hist. of the Two Orphans III 112: Taking a dirty paper out of her bosom, in which was written the following words: Tape, glim, rushlight, white port, rasher of bacon, gunpowder, slug, wild-fire, knock-me-down, and strip-me-naked.