The former Tottenham frontman netted one from the spot in the first half before netting a fine individual goal after the break.
Further goals from the influential Andy Reid and debutant Michael Turner, facing his former club, capped a fine second half performance from Steve Bruce's side.
Bruce asked Kieran Richardson to fill in at left back in place of the injured George McCartney, whereas Frazier Campbell - making his first Premier League start for the Black Cats - partnered Bent up front in favour of Kenwyne Jones, as Turner slotted in alongside Anton Ferdinand at the heart of the defence.
The first half was a scrappy affair with Phil Bardsley having the hosts' first effort with a wayward shot off target after eight minutes.
The visitors responded and Geovanni had a shot tipped around the post by Craig Gordon from 22 yards.
Moments later the Black Cats keeper saved Stephen Hunt's volley from an acute angle after 33 minutes. The Sunderland goalkeeper was then called into action four minutes later but comfortably saved Kamil Zayette's glancing header, from Hunt's free-kick.
But Sunderland took the lead when Reid's outswinging corner was handled by Craig Fagin and Bent, who had been relatively quite until then, tucked the penalty away with aplomb curling away from the goalkeeper's right hand into the corner.
Zayette levelled two minutes before the break when he rose above less than convincing Black Cats' challenges to head past Gordon from five yards.
The second half began with a bang and, within three minutes of the restart, Hull shot stopper Boaz Myhill had bravely thwarted Campbell at his feet; Dawson had fouled Bent for a blatant penalty before Reid blasted the hosts ahead from left of centre following Phil Bardsley's fine cross from the right.
England wannabe Bent then ensured the points remained on Wearside in the 66th minute when he latched on to Ferdinand's searching ball over the top.
He advanced into the box, kept a cool head and thrashed past Myhill from eight yards.
The Sunderland supporters then taunted the opposition manager Phil Brown with Browny, Browny what's the score
The South Shields-born Hull boss had earlier provoked he ire of home followers when he responded to travelling fans' requests for a wave which he happily replied with somewhat over zealous exuberance.
Former Tiger Turner then rubbed salt further into Brown's wounds when he powerfully headed Reid's corner in from close range with just over 15 minutes left.
Sunderland: Gordon, Bardsley (Mensah 77), Turner, Ferdinand, Richardson, Malbranque (Da Silva 81), Cattermole, Cana, Reid, Campbell, Bent (Jones 73). Subs (not used): Carson, Henderson, Nosworthy.