Pearson has just been overlooked for the West Brom job, taken by former Town player Tony Mowbray, and was also in the running for the Ipswich post in the summer, before Jim Magilton was chosen to succeed Joe Royle.
Magilton may have topped Pearson on that occasion, but on the field there was only ever one winner with a woeful Ipswich not managing a single shot on goal, their strike only coming courtesy of a freak Chris Perry own goal.
That levelled matters at 1-1 after Diomansy Kamara's opener, but Kevin Phillips restored the lead before half-time and went on to claim a clinical hat-trick, as well as putting striker partner Kamara through for another.
Town were dismal in all departments as they crashed to a second straight loss, following a six-game unbeaten run previously, while the Baggies were left to celebrate a first away win since January.
The game began quietly, with two Darren Carter shots for West Brom, one wide and one saved easily by Lewis Price, while Alan Lee pounced on a loose ball before firing wide for Town.
Town appealed for a penalty when Kamara appeared to nudge over Jason De Vos at a corner, before Jason Koumas curled an effort not far over after being found by Carter in a quick break.
Kamara volleyed across goal, just out of reach of Phillips, before West Brom went ahead on 29 minutes when Koumas' superb volleyed pass fell into the path of Kamara, who left Richard Naylor for dead before firing low past Price.
Phillips stabbed wide from a couple of yards from a Martin Albrechtsen knock-down at a corner before Town levelled on 36 minutes with a freakish own goal.
Billy Clarke chased a Simon Walton flick-on and Curtis Davies came across to make a well-judged sliding tackle. Unfortunately for the visitors, the ball fired into the shins of Perry and deflected past a bemused Pascal Zuberbuhler from 20 yards.
Price saved a curling Koumas free-kick before a needless Naylor foul on Koumas gave the Welsh international the chance to curl in another dead ball on 40 minutes for the unmarked Phillips to glance in off the post.
Any chance of a home fightback was snuffed out on 53 minutes when West Brom broke from a Town corner, Koumas' superb crossfield ball found Zoltan Gera and his pinpoint cross was headed into the roof of the net by Phillips.
Amazingly it was 4-1 to the visitors three minutes later when Phillips was allowed to turn on a throw from the halfway line and play in Kamara, who coolly rounded Price and slotted home.
There was a nasty flare-up on 66 minutes when Jonathan Greening lunged in on Town sub Dean Bowditch and sparked a mass confrontation involving the majority of the players.
Greening was fortunate to escape with a yellow card, while Naylor was also booked for appearing to raise his hands during the pushing and shoving which followed the foul.
The rest of the game saw West Brom happy to play out time, but they broke from another Ipswich corner in stoppage time and Phillips curled home magnificently from the edge of the box after turning Alex Bruce to seal a comprehensive and totally deserved victory.