Green’s Dictionary of Slang

(US) a Chinese restaurant.

1927		Times Herald (Olean, NY) 31 Jan. 13/2: The barkers make promise of strange sights and adventures that end in a made-to-order jaunt through chow mein parlors and a public joss house.
1937		Cincinnati Enquirer (OH) 5 Sept. 4/3: All sorts of sacrifices are being made by laundrymen, proprietors of one-room, walk-down chow mein parlors and peddlers of tiger bone wine.
1944		Palm Beach Post (FL) 24 Dec. 4/6: He’ll speak his mind in a Wentworth Street chow mein parlor in Chicago after the war.
1978		S. Longstreet Straw Boss (1979) 378: In a democratic organization we don’t ask if they [...] ever shook down a chow mein parlor.
1981		Herald (Crystal Lake, IL) 14 Jan. 18/1: The all too common chop suey and chow mein parlors and takeout diners.