Ollie Watkins’ neat turn and finish fired Villa into an early ninth-minute lead before Douglas Luiz doubled the advantage with a close-range finish on the stroke of half-time.
The hosts then made sure of all three points with two goals in three minutes early in the second half – Philippe Coutinho capping an impressive display with a smart finish from a tight angle before Danny Ings, who also registered two assists against his former club, swept home a fourth.
With the Villans purring in attack and Saints goalkeeper Fraser Forster coming to the visitors’ rescue on numerous occasions, Steven Gerrard’s side also kept a valuable clean sheet, Emi Martínez making a superb one-handed save to thwart Che Adams and cap the perfect afternoon for the home side.
It was a second successive victory and clean sheet for Villa, who recorded their first home win since early December and first over in-form Southampton in B6 since 2004.