First recorded by Eddie Williams & His Brown Buddies (1949).
Hit version by Louis Jordan & His Tympany Five (US #21/R&B #1 1949).
http://youtu.be/Se9mX60LCrY
From the wiki: “‘Saturday Night Fish Fry’ was written by Ellis Walsh and adapted by Louis Jordan (who received co-writing credit), and first recorded in 1949 by Eddie Williams & His Brown Buddies featuring the talk-singing vocals of Walsh. The act had recently had a hit with ‘Broken Hearted’; ‘Saturday Night Fish Fry’ was intended to be the Williams’ band’s followup. However, the acetate for the William/Walsh recording found its way to Louis Jordan’s agent and, as Williams later recalled, ‘They got theirs out there first.’
“Jordan reconfigured the song, taking the song’s ‘hook’ and signing it twice after every other verse. The arrangement was also more propulsive, too; Williams’ shuffle was replaced by a raucous, rowdy jump Boogie-woogie. ‘Saturday Night Fish Fry’ has been called one of the first Rock ‘n roll records. No less than Chuck Berry has said ‘Louis Jordan was the first one that I hear play rock and roll.'”
Louis Jordan & His Tympany Five, “Saturday Night Fish Fry Parts 1 & 2” (1949):