On a glorious summer evening, Malan, who has shone in the two shorter formats of the game this season, and Joe Denly (52 not out) helped the Panthers chase down a formidable Essex total in front of 20,000 spectators at Lord's.
The Eagles had earlier won the toss and elected to bat, posting a solid 170 on a decent track.
However, the Panthers led by Malan - whose 86 came in just 55 balls, including 10 fours and 3 sixes - at the top of the order were up to the task and got home with two balls to spare in their second twenty20 at Lord's this season.
The win will have pleased captain Neil Dexter after his side suffered a defeat to Sussex Sharks in their previous match.
Their final Twenty20 encounter at the Home of Cricket this sees Middlesex take on Surrey in the battle of London on 25 July. Tickets are available here.