Sweet goals in the space of four minutes just after the half-hour mark from full home debutant Ike Ugbo and Harvey Barnes, who marked his full debut by scoring a blistering volley, put the Reds 2-0 ahead at the interval.
George Moncur crowned a wonderful afternoon for the hosts, with a fine third goal midway through the second half.
Sunderland, backed by a big travelling contingent, started well enough, but the Reds regrouped, with the best chance of the first half-hour seeing Dutch keeper Robbin Ruiter block Moncur's stinging drive.
Just after the half-hour, the increasingly dominant Reds took the lead, when Ugbo bundled in at the far post after Barnes' inviting centre, following good work by Hammill.
Four minutes later, the Reds doubled their money with an outstanding volley from Barnes, with the increasingly influential Hammill providing the cross.
Barnsley survived a scare on 41 minutes when Liam Lindsay picked up just a caution after fouling James Vaughan, in full-flight and haring towards goal, with Aiden McGeady wasting the free-kick right on the edge of the box.
The Reds made the game safe with a lovely third midway through the second half from Moncur, whose curled finish was exquisite after tidy work in the build-up from Ugbo.
Both Paul Heckingbottom and Simon Grayson had plenty of food for thought in terms of their team selections after witnessing their respective teams produce lacklustre performances seven days earlier.
Heckingbottom was bold in his calls, bringing in Ugbo for a full home debut at the expense of the experienced Tom Bradshaw, while Barnes was handed a full debut, replacing Ryan Hedges.
Liam Lindsay was also a surprise name in the starting line-up after making a quicker than expected return from a groin injury.
Black Cats chief Grayson promoted Bryan Oviedo and Robbin Ruiter to the starting line-up and on the evidence of today it was Heckingbottom who certainly came up trumps with his moves, while his Sunderland counterpart has plenty to ponder after another poor performance from his side.
The 4,249 visiting contingent showed what they thought of it all, with chants of 'You're not fit to wear the shirt' to the Sunderland players at intervals, with the away end virtually empty by the time that the final whistle arrived.
The Reds, by contrast, rewound the clock to some highs of 12 months ago, with the likes of Hammill and Moncur enjoying themselves immensely, with the hosts ending a fraught summer in encouraging fashion - with a clean sheet being an added bonus.
Barnsley: Davies; Pearson, Jackson, Lindsay, McCarthy; Williams; Hammill (Thiam 90), Potts, Moncur, Barnes (Hedges 66); Ugbo (Bradshaw 72). Substitutes unused: Townsend, Pinnock, Mowatt, Bird.
Sunderland: Ruiter; Jones, Browning, Kone, Oviedo (Matthews 81); McGeady, Cattermole, N'Dong, Honeyman (Khazri 65); Vaughan (Gooch 55), Grabban. Substitutes unused: Steele, O'Shea, Gibson, Asoro.
Referee: C Kavanagh (Lancashire).
Attendance: 15,697 (4,249 Sunderland supporters).