My rebbetzin gave me this recipe a few years ago. I had a disastrous Rosh Hashana in the honey cake department, went to a break-the-fast at her place, and she had this AMAZING cake. I've made it every year since and make it in the off-season, too. This is one of those cakes that gets better as it ages, so if you want to make it a day or even two ahead, it'll actually taste better. She says it's based upon a recipe in Marcy Goldman's cake in A Treasury of Jewish Holiday Baking, but that thing's out of print. I did find a copy of it, purchased it for the recipe, and found that it was.. lacking.. in the spice department.
I haven't put in the optional whiskey to date, but I believe it's more traditional to use it. I've just never had it around.
I also like using bundt pans for this. Did you know Hadassah asked NordicWare to make the original bundt pan?