The Brit inherited the race lead after a rare mistake from Mahindra Racing's Lucas di Grassi, who had secured the Julius Baer Pole Position earlier in the day. In his first race for the Mahindra outfit, the Brazilian accidentally let Dennis through on Lap 12 of the 41-lap race.
From there, the 27-year-old produced an energy-management masterclass in the Andretti-run Porsche 99X Electric finishing the race with a seriously impressive 7.816s lead to second place TAG Heuer Porsche's Pascal Wehrlein. This gap from first to second is the seventh largest of all time in Formula E's nine seasons.
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"To win by that margin, to start on the front row and get a Porsche [powertrain] one-two is absolutely incredible," Dennis said about his fourth Formula E victory. "Big shout out to my team."
Dennis also described how challenging these Gen3 beasts are to tame, stressing how demanding the race was.
"These cars are so hard to drive physically. Obviously, with a lower grip as well, it just makes everything so challenging but even more rewarding when you win you win by 7.5 seconds.
"The fans here have just been sensational on that final lap. I could really hear them cheering."
This will be the third consecutive year Dennis will compete with the Andretti squad in Formula E, admitting that he'll be treating the team to some well-earned tequila tonight.
"My team and my team and I just have such a good relationship together," he continued.
"We just worked so well. When it's up against us like it was in the qualifying, we turned it around and made some small adjustments for the race and absolutely nailed it. So big kudos to my guys. I'm nothing without them.
"This is just more repayment for them. I hope to have more success because obviously, Saudi is not far away."
Dominant Dennis will be hoping to replicate the success of this first race when Formula E heads to Diriyah on 27 and 28 January, later this month.