On both occasions Vettel spearheaded a Red Bull one-two, finishing a quarter of a second faster than team-mate Mark Webber in the opening session at the Hungaroring.
Come the second session, and the switch to the soft Pirelli tyre - the quicker of the two compounds being used this weekend - Vettel improved his time by 1.5secs with a lap of one minute 21.264secs.
Webber at least managed to close the gap to just 0.044secs come the conclusion, but Vettel is so far looking on course to increase his current championship lead heading into Formula One's summer break.
As in FP1, a Lotus was third on the timesheet in FP2, but it was that of Romain Grosjean and not one of Vettel's two main title rivals in Kimi Raikkonen, who was down in eighth and 0.747secs off the pace.
Ferrari's Fernando Alonso, 34 points adrift of Vettel after nine of the 19 races, was again fourth fastest in his Ferrari, 0.162secs down, with team-mate Felipe Massa next up in fifth.
Mercedes duo Lewis Hamilton and Nico Rosberg improved to fifth and sixth, the former chalking up a day-high total - and a race distance - of 70 laps.
That was primarily due to Mercedes coming into this race on the backfoot after being banned for last week's young driver test at Silverstone, where Pirelli's new range of tyres were initially tried.
Following a series of blowouts during the British Grand Prix last month, Pirelli were rapidly forced to revise their tyres, opting for a solution that comprises last year's structure with this year's compounds.
For Hamilton and Rosberg, the two sessions have been all about obtaining as much information as possible ahead of qualifying and the race.
At present, the team's run of six pole positions in the last seven races appears under threat by Red Bull and Vettel, who has won two of the previous three grands prix to open up his advantage over Alonso, with Raikkonen 41 points adrift.
Hamilton finished just over half a second down on Vettel, with Rosberg 0.727secs back, while McLaren's Jenson Button and Adrian Sutil in his Force India - on the occasion of his 100th grands prix - completed the top 10 behind Raikkonen.
Paul Di Resta, who struggled in session one with set up and found himself 1.5secs behind team-mate Sutil, at least improved in FP2, moving up to 11th on the timesheet and 0.222secs down on the German.
Marussia's Max Chilton, who sat out the morning run in favour of reserve Rodolfo Gonzalez, was slowest of all, 5.383secs behind Vettel, and more importantly 1.5secs down on team-mate Jules Bianchi.
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