Conversation so far:
How are Minit and Instant Records connected to Allen Toussaint?
In 1960, Joe Banashak, of Minit Records and later Instant Records, hired Toussaint as an A&R man and record producer.
What records did Allen Toussaint produce?
Southern Nights is a 1975 R&B concept album by Allen Toussaint.
Did Allen Toussaint discover or sign any singers?

Question: What was his most successful recording?
Self-contained rewrite: What was Allen Toussaint's most successful recording?