Coach Daniel Anderson and skipper Paul Sculthorpe lift the trophy
Huddersfield 12 (6)
Tries: Aspinwall, Paul
Cons De Vere 2
St Helens 42 (12)
Tries: Talau, Long, Wilkin 2, Fa'asavalu, Lyon, Cayless
Cons: Lyon 7
St Helens claimed their fifth Challenge Cup trophy in just 11 years with a seven-try victory over Huddersfield in Saturday's final at Twickenham.
The Giants took a shock lead after just six minutes through Martin Aspinwall, but Saints took command after the break to justify their tag as big favourites.
Jon Wilkin bagged two tries while Jamie Lyon finished with 18 points thanks to a try and seven conversions.
Sean Long was named Lance Todd Trophy winner for a record third time.
The Giants made a hugely encouraging start as they attempted to defy the odds stacked against them.
I'm thankful that I'm playing in a legend of a team and playing off great forwards
Lance Todd Trophy winner
Saints stand-off Leon Pryce made a mess of the kick-off, the ball ricocheting off his shins and straight back into the arms of the opposition.
Brad Drew made the most of the early opportunity to attack and was held up just short of the line in the first minute.
But team-mate Aspinwall was not going to be denied five minutes later.
After Drew had danced his way past several St Helens defenders from 35 metres out, he passed to Michael De Vere, who fed Aspinwall on his left.
De Vere slotted a difficult conversion from the touchline to make it 6-0.
Huddersfield continued to excel in the opening 20 minutes, while Saints were uncharacteristically sloppy.
Jon Wilkin overcame a broken nose to play a key role for St Helens
But the favourites were level on 21 minutes when Willie Talau crossed over from Paul Sculthorpe's kick through and Jamie Lyon knocked over the conversion.
Giants full-back Paul Reilly saved a certain Saints try on 29 minutes with a brilliant diving tackle on Ade Gardner, who had out-paced Chris Nero down the right touchline.
But Huddersfield were powerless to stop man-of-the-match Long going over four minutes before the interval.
Lyon split open the Huddersfield defence on the right, offloading to Gardner, who popped the ball out to Long for the easiest of scores.
Once again, Lyon added the extras to make it 12-6.
Wilkin, sporting an improvised bandage across his face to stop the bleeding from his broken nose, put Saints firmly in the driving seat with his side's third try on 46 minutes.
Samoan Maurie Fa'asavalu powered his way through the Huddersfield defence before finding James Roby on his outside.
The youngster was tackled, but Saints quickly swooped to extend their advantage through Wilkin.
Fa'asavalu then put Saints within sight of another Cup win when he dived on Roby's kick on 52 minutes, with Lyon's fourth successful kick making it 24-6 to Saints.
Huddersfield's resistance was finally killed off by tries from Lyon, the reigning Man of Steel, and Wilkin.
Robbie Paul grabbed a late consolation with a try under the posts from Drew's kick, but Jason Cayless extended the lead again with his side's seventh try.
Lyon made it seven successful kicks from seven attempts to take his points tally for the game to 18.
Huddersfield: Reilly, Aspinwall, Nero, De Vere, Donlan, Thorman, Paul, Jackson, Drew, Gannon, Crabtree, Raleigh, Wild. Replacements: Snitch, Jones, Smith, McDonald.
St Helens: Wellens, Gardner, Lyon, Talau, Meli, Pryce, Long, P. Anderson, Cunningham, Cayless, Wilkin, Sculthorpe, Hooper. Replacements: Gilmour, Roby, Graham, Fa'asavalu.
Referee: R Silverwood (Dewsbury).