One thing you will see repeated over and over in southern cooking is the use of the The Trinity - onion, celery and bell pepper - generally used in equal amounts, but not always.
Far as I know, it originated in Cajun and Creole cooking in Louisiana, but is the base of many, many dishes all over The Deep South. Hardly a southern kitchen is without these three primary ingredients pretty much all the time. They are simply a kitchen staple to us.
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