The first-ever, slow, raw performance of Big Legged Woman (written by Johnnie Temple) was recorded at the 1976 Stuttgart concert. Just as in the 1978 Boston show it was used as an intro to What'd I Say.
The song is best known in Freddie King's version, but Ray stayed much closer to the slow version of Muddy Waters, giving it exactly the dirty blues-treatment it deserves.
You can listen to both recorded performances here (Stuttgart) and here (Boston). In both cases the audio quality is mediocre at best.
'76 LC Stuttgart
'78 LC Boston