You have the normal recipe. Instead of using all water, only use 1/2 to 1/3 of the designated amount of water, the rest is vodka. Hard liquor doesn't freez, so if you use ALL Vodka, it won't get jell-o like.
It was probably already at the temperature of being Jello, and when he added more mix and water, it wouldn't take nearly as long. Only way I can justify it, actually.