Duncan Watmore scored his first goal since suffering two ACL injuries as Sunderland moved to within one win of Wembley.
The Black Cats made light work of Manchester City U21s, with Lynden Gooch also scoring a welcome goal to seal a 2-0 win.
It should have been more as Sunderland created a host of chances, picking apart their opponents and forcing Daniel Grimshaw into a number of saves.
While Manchester City were weakened by Pep Guardiola calling up a number of youngsters for a Carabao Cup game on Wednesday night, they played with typical poise and composure on the ball.
Sunderland, though, looked themselves to be enjoying the extra time and space in possession right from the off.
They enjoyed most of the possession in the early stages, even if Dutch forward Jayden Braaf had the first shot in anger, firing wide of Robbin Ruiter's far post from a narrow angle.
Watmore was enjoying a switch to the right wing and after a good spell of pressure from the Black Cats, he scored the opener with a fine finish.
Dylan McGeouch did well to find his way to the edge of the area, where he played a smart one-two with Benji Kimpioka.
The ball broke for Watmore who confidently fired into the top corner.
He went close to a second within minutes when McGeouch again played a good ball into the box, Watmore stinging the palms of Daniel Grimshaw with a firm effort.
When Bryan Oviedo hit the bar with a dipping free-kick soon after, the Black Cats looked in complete control.
City rode that storm and started the second half the better of the sides, though Sunderland were largely comfortable and happy to let the visitors play near their own halfway line.
It was the Black Cats who came closest to scoring when Lee Cattermole broke up a City move, finding Watmore as he broke towards goal. A clever lay-off found Luke O'Nien who flashed
one inches wide of the post.
After an excellent showing Watmore was replaced by Lynden Gooch, who promplty put his side 2-0 up.
In trademark fashion he cut in from the right flank and curled a shot into the far corner.
Sunderland were utterly dominant, O'Nien almost scoring a fine goal when his long-range shot was spilled by Grimshaw, who only just recovered to prevent the ball spilling over the line.
He then had to get down well to prevent Kimpioka from scoring after the Swede burst into the penalty area.
O'Nien forced another good pair of saves from Grimshaw as Sunderland ended the game with a flourish.
The prospect of a grand day out in March is fast becoming an enticing reality.
Sunderland XI: Ruiter; Matthews, Ozturk, Baldwin, Oviedo; Cattermole (Robson, 75), McGeouch; Kimpioka (Connelly, 89) O'Nien, Maguire, Watmore (Gooch, 60)
Subs: Stryjek, Flanagan, James, Neil
Man City U21s: Grimshaw; Frimpong, Rosler, Harwood-Bellis, Ogbeta (Diounkou, 45); Pozo, Dele-Bashiru, Doyle (Bernabe, 74); Garre, Braaf, Touaizi (Knight, 78)
Subs: Wilson, Ogunby, Moulden, McDonald
Bookings: Cattermole, 17 Ogbeta, 31 Pozo, 89 Braaf, 90