Goals from Nabil Bentaleb, Nacer Chadli, Harry Kane and substitute Roberto Soldado avenged October’s Premer League defeat against the same opposition, and a two-legged semi-final against League One Sheffield United is now all that stands between Spurs and Wembley.
Bentaleb scored his first senior goal at club level to hand Tottenham a 1-0 lead before the break, taking advantage when young goalkeeper Jak Alnwick flapped at Christian Eriksen’s corner.
Just 34 seconds into the second half Spurs double their lead. Nacer Chadli picked up possession just outside the area and struck a low right-foot drive into the bottom corner.
Kane bagged his 13th goal of the season with a sweet strike. It continued the England U21 international’s record of scoring in every round of this season’s competition and his replacement Soldado added extra gloss, slotting home from close range after Eriksen’s initial effort was saved.
While things are on the up for Tottenham,defeat was hardly the visitors’ ideal preparation for the Tyne-Wear derby against Sunderland this weekend.
It was a result which looked likely from early on, with Benjamin Stambouli, one of six Spurs changes, seeing a long-range effort loop onto the roof of the net via a deflection.
Chadli got away the evening’s first shot on target after meeting a lovely Andros Townsend pass, before Kane almost latched onto a fine cross-field ball from Danny Rose.
Townsend shot over as Spurs continued brightly and took the lead 18 minutes in after a moment that will haunt Alnwick.
Newcastle’s third-choice goalkeeper inexplicably fumbled an Eriksen corner and Bentaleb reacted quickly to scoop home in front of the befuddled visiting support.
It was a lead Spurs deserved but one which it looked like they were easily capable of squandering.
Michel Vorm did well to prevent Moussa Sissoko ending an impressive run with a thumping goal from distance shortly before the opening goal, which was followed by a major let-off for Pochettino’s men.
Yoan Gouffran was afforded time to swing in a cross from the right which found Emmanuel Riviere unmarked, only for the frontman to direct wide from close range, unaware the offside flag was raised.
Sissoko stung the palms of Vorm from 25 yards as Newcastle’s search for a leveller continued – a task Spurs attempted to make more difficult as half-time approached.
Kane looked likeliest to provide a second Spurs goal and, thanks to Gouffran’s shocking backpass, was allowed to burst forward and unleash a fierce drive just wide.
The academy graduate was proving a nuisance and looked to have won a penalty after going down under pressure from Fabricio Coloccini, only for referee Andre Marriner to infuriate Pochettino by waving play on.
If the Spurs head coach was concerned about that costing his side, those fears were alleviated seconds into the second half.
When the sides last met here Sammy Ameobi’s goal moments after the restart was the catalyst to Newcastle’s win, whereas this time it was the hosts celebrating when Chadli’s low strike crept past Alnwick.
It was a sucker punch Alan Pardew’s men were unable to recover from, with Remy Cabella and Riviere somehow unable to turn home Ayoze Perez’s cross.
The Magpies’ need for a goal was leaving spaces at the back and Vlad Chiriches forced a save from Newcastle’s third-choice goalkeeper.
A goal-line clearance from Haidara prevented Vertonghen extending Spurs’ lead, but fans’ favourite Kane soon added a third, collecting a pass from Townsend to coolly slot home.
It was Kane’s last action of the night, but his replacement carried on where he left off as Soldado reacted quickly to tap home after Alnwick parried Eriksen’s fizzing drive.
Townsend and Soldado had attempts shortly afterwards and, at the other end, Vorm was held firm under pressure from Perez and substitute Adam Armstrong as Spurs secured their semi-final spot for the first time since 2009 when they were beaten in the final on penalties by Manchester United.
Tottenham: Vorm (7) Chiriches (7) Fazio (5) Vertonghen (6) Rose (7) Bentaleb (6) Stambouli (6) Chadli (7) Eriksen (7) Townsend (8) Harry Kane (9).
Subs: Dembele (7) Soldado (7) Capoue (4).
Newcastle: Alnwick (5) Dummett (5) Coloccini (6) Williamson (7) Haidara (6) Colback (6) Sissoko (7) Perez (6) Cabella (5) Gouffran (6) Riviere (5).
Subs: Armstrong (7) Anita (5) Vuckic (4).
MAN OF THE MATCH