Green’s Dictionary of Slang

macaroni n.4

[joc. ext. of mack n.2 (1)]

(US) the middleman, usu. a pimp, who stands between the client and prostitute.

[US]B. Rodgers Queens’ Vernacular 129: macaroni 1. (pros sI, fr black sl; cf Fr argot mec = pimp) a pimp.
[US]Maledicta VII 23: Macaroni […] is also slang for a dude or fop, and lately a name for a black pimp.

In phrases