Oddly my mustard Mayo decree is more Deep South and from black cooks
Mid south Nashville where I am now it’s not as common
For me the south starts when I cross the Tn river on eye sixty five headed to Mississippi
North Alabama is much more southern than Nashville
Same when headed west on forty
West tennessee is like Mississippi
West side of same river
LOL - when I was living in Louisiana, I considered everything north of I-10 to be southern Arkansas, and joked about all those yankees way up north in Shreveport