Deflected efforts either side of halftime from Chelsea captain John Terry and leading scorer Diego Costa dashed Tottenham's hopes in the all-London League Cup final.
Chelsea had suffered a chastening Christmas defeat to the same opposition in the English Premier League, with Harry Kane starring, but the promising young English striker was kept largely quiet in the showpiece occasion.
The first half saw Tottenham edge the possession and carry more of the attacking threat, with Dane Christian Eriksen's free kick rattling the Chelsea crossbar.
But chances for either side from open play were in short supply and it was from a free kick that Chelsea went ahead just before the break.
Willian's delivery from the right brushed Danny Rose's head and fell invitingly to Terry whose shot went into the net after taking a deflection off Eric Dier.
Tottenham might have felt hard done by and the sense of injustice would have deepened on 56 minutes as Cesc Fabregas found Costa down the left and his firm strike took another wicked deflection, this time off Walker, who was credited with the own goal, to leave goalkeeper Hugo Lloris with no chance.
It seemed to take the sting out of the Tottenham challenge and although Kane had a late half chance, it was Terry who typically snuffed out the threat with a timely tackle.
It was the fifth time Chelsea had lifted the English League Cup and third under Mourinho.
The Portuguese claimed it in his first season with the west London club in 2005 and after returning to the Stamford Bridge hot seat last season has broken his mini-trophy drought.
Mourinho, whose side is also well-placed to go through to the quarterfinals of the Champions League, was clearly reveling in his latest success, his 21st career trophy as a manager.
"'It is important to feel like a kid at 52 years old," he said.
Man of the match Terry is hoping it will pave the way for further triumphs.
"It's the first trophy this season and it's massive. It meant an awful lot to us when we won it in Jose's first year in 2005 as well," he said.
"That could be the start of something very good. We have to kick on and we have got the league to focus on, but it's a great day and a great win."
Man City blow
Chelsea was also boosted by an earlier result in the EPL as its nearest title rival Manchester City was beaten 2-1 at Liverpool.
City had hoped to cut the gap at the top on Chelsea to just two points with a win at Anfield, but instead suffered a chastening reverse.
Jordan Henderson put Liverpool ahead with a thumping shot after just 11 minutes only for Edin Dzeko to draw City, defending the EPL title, level midway through the first half.
Liverpool, looking to boost its own chances of Champions League football next season, dominated after the break and deservedly took three points after Philippe Coutinho scored a superb late winner with a curling shot which flew past Joe Hart.
Arsenal stayed third by beating Everton 2-0 with Olivier Giroud and Tomas Rosicky scoring late in each half to give the Gunners a boost after a Champions League defeat to Monaco in midweek.