In a stand mixer fitted with the paddle attachment, mix the soft cream cheese and brown sugar until smooth.
In a separate bowl combine the pumpkin puree, eggs, sour cream, vanilla and bourbon. Slowly add to the cream cheese mixture, scraping down the sides often.
In another bowl whisk together the sugar, starch, spices and salt. Add this to the cream cheese and pumpkin mixture. Beat on medium/low speed until well combined, scraping down the sides often.
Pour into prepared pan. Gently tap the cake pan several times on the counter to bring any air bubbles to the surface.
Bake in a water bath and with a foil tent as shown in previous post on Key Lime Cheesecake, for about 45-60 minutes or until set, slightly puffy and no longer wet looking. While the cake is baking mix together all the ingredients for the topping, set aside.
Once the cake is fully cooked remove the foil and very gently spread the on the sour cream topping with an Offset Spatula. Bake uncovered with the topping for an additional 5 minutes. Remove the cake and allow to cool slowly still in the water bath. Carefully run a thin blade knife around the edge of the warm cake so that it won’t crack. Put in the refrigerate to cool for at least a couple of hours!