The Bluebirds picked up their third victory in four Championship matches under Slade as a flurry of goals after the break saw them claim the points on home turf.
While praising Leeds for their style of "unpredictable" football, Slade believes that his players coped well with what was in front of them.
"It was a bit of a non-event of a first half in many ways, with not much in it and not too many chances. I don't think anyone expected that in the second half: four goals and an entertaining game," he told BBC Sport.
"The players put a really good shift in, and particularly in the second half we needed to find a little bit more energy, a little bit more intensity.
"The game was always a worry for me. They are very unpredictable in the way they play. They've got some talented players, so it was important for us to be compact and keep our discipline."
Cardiff are next in action on Tuesday night when they make the trip to Bolton Wanderers.