The German was in a class of his own under the Marina Bay lights, winning by a massive 32.6 seconds over Fernando Alonso and boosting his championship lead on the Ferrari driver from 53 points to 60 with six races remaining.
"We are in a very good position. To be honest I am not looking at the championship too much," Vettel said. "I am just enjoying it at the moment. Days like today and yesterday are what it is all about."
Lotus' Kimi Raikkonen was third, ahead of the Mercedes pair Nico Rosberg and Lewis Hamilton in fourth and fifth respectively.
Starting in pole, Vettel lost the lead at the first corner to Rosberg but took it back as the Mercedes driver ran wide at turn two. Even a safety car period just before half distance, which eroded his 12-second lead, could not prevent another Vettel victory.
"The start was quite hairy, Nico had a good start, but fortunately he went a little too deep and I was able to get him back," Vettel said.
"With the safety car, it was difficult but we came back ... we had very, very good pace."
Red Bull teammate Mark Webber had sharply different fortunes in the race. As the Australian was threatening Raikkonen in the closing stages, he experienced an engine failure that saw him pull off the track with his car in flames on the closing lap.
Webber hitched a ride back to the pits on the sideboard of Alonso's Ferrari, and that was enough for both drivers to receive a reprimand from stewards as three cars had to take evasive action as the Ferrari stopped and the Red Bull man clambered on board.
For Webber, the reprimand has serious consequences because it is his third of the season, meaning he will receive a 10-place penalty on the grid at the next race in South Korea.
Alonso was in a generous mood after an impressive showing.
The Spaniard got a superb start, going around the outside of several drivers to vault from seventh to third after two corners, and capitalized on the emergence of the safety car by pitting for his final stop, taking on a set of the harder tires which he drove for the last 36 of 61 laps.
"We knew we didn't have the pace today, we had to invent something," Alonso said. "I had a good start and a different strategy ... it tastes like a victory to us."
Raikkonen's participation in the race had been in doubt due to a back injury that affected him badly in Saturday's qualifying, but the Finn sliced his way through the field in the latter half of the race to move up from 10th to a podium finish.
"Luckily not too much (pain during the race) but now, afterwards, it's not 100 per cent but I have time to rest and get it right," Raikkonen said. "Third place — we could not have expected any more today."
Ferrari's Felipe Massa was sixth, ahead of the McLaren pair Jenson Button and Sergio Perez in seventh and eighth respectively, with Sauber's Nico Hulkenberg and Force India's Adrian Sutil completing the top ten.
Vettel's victory was his third in a row in Singapore, his seventh of the season, and 33rd of his career, moving him out of a tie with Alonso and into outright fourth place on the all-time list behind Michael Schumacher, Alain Prost and Ayrton Senna.
Vettel also won from pole in the previous F1 race in Italy and took the lead on the opening lap of the Belgian GP, meaning he has now led effectively from start to finish in three successive races.
With such dominance over his dispirited rivals, only an extraordinary turnaround can prevent Vettel winning a fourth-straight championship, joining Schumacher and Juan Manuel Fangio as the only men to achieve that feat.
Ferrari had said prior to the race that the result in Singapore would determine whether to continue development of the car or to turn all resources to the radically redesigned 2014 vehicle. Alonso's second placing will likely be enough to keep Ferrari's mind on this year, but the Spaniard was realistic about his fading title hopes.
"The gap is still increasing every weekend and now it's 60 points," Alonso said. "We need to be honest with ourselves. We need a lot of luck every weekend if we are one second (per lap) off their pace."Suggest a correction