I never use a recipe since I've been making it forever. It was late and I'm lazy so I found that link. This one is close, but after looking at it I'll make the following observations -

It calls for sugar. No way I'd add sugar as its plenty sweet already due to the concentrates. Unless of course you've got a house full of foo-foo drink swilling chicks, they'd probably like it. But our assembly is staffed with highly seasoned professional alcoholics. Sugar? We don't need no stinking sugar! And if you've got a house full of foo foo drink swilling chicks, can I come over next year?

I make my own tea, unsweetened. I use 2 or 3 teabags per cup and let it steep a while.

I put a hell of a lot more bourbon in. Typically we run out early so every year I make it stronger in an attempt to slow down its consumption. It never works, so it just keeps getting stronger. I use empty plastic milk jugs and start with half bourbon. I usually make two gallons. It takes longer to freeze up but it goes down just as fast.

Along those lines, if you've already ruined your liver you might like to try this...float a shot of fresh bourbon on top of the slush after you've filled a glass. It looks nice and it tastes great! It will however, start to thaw the slush in the glass. So let it sit for a just a minute. Once its imbued with citrous goodness just slurp that shot right off the top.