The former Norwich assistant boss was in the stands for the League One clash in Essex to see his new charges make it five wins in six games thanks to Ian Craney's goal after 49 minutes.
The midfielder netted after Michael Collins sent in a low cross from the left byline and the ball went past a stationary Steve Mildenhall and Craney tapped into the open goal from four yards for his sixth of the season.
Southend should have equalised from the penalty spot eight minutes from time after Kevin Betsy was brought down by Robbie Williams.
But substitute striker James Walker hit a daisycutter of a spot-kick which keeper Alex Smithies easily saved to ensure back-to-back wins for the Terriers.
Earlier, Smithies had denied Adam Barrett and was relieved to see a Francis Laurent shot go inches wide after he was beaten.