Optional: whole pecans and a jar of Dulce de Leche to decorate the top of the cheesecake with. You could also use whipped cream, if you wish.
Preheat oven to 350 degrees F.
combine the Cinnamon Chex crumbs, ground pecans, 2 tablespoons granulated sugar, 2 tablespoons brown sugar, and the melted butter and mix well. Firmly press into one 9-inch springform pan.
Combine 3/4 cup granulated sugar, pumpkin puree, 3 egg yolks, spices and salt in a medium bowl. Mix well and set aside.
Beat the cream cheese with an electric mixer until light and fluffy; gradually add 1/4 cup plus 2 tablespoons granulated sugar and mix well. Add the whole egg, remaining egg yolk, and the whipping cream, beating well. Add cornstarch and vanilla extract, beat batter until smooth. Add pumpkin puree mixture and mix well. Pour batter into prepared pan. (Note: I placed my springform pan on a cookie sheet with sides, and I'm glad that I did, because I had some liquid leaking from the springform pan. Keep that in mind!).
Bake in preheated oven for 50-55 minutes. Do not overbake. Center may be soft but it will firm up when chilled. At this point, turn the oven off, and open the oven door, but allow cake to remain in oven for the next hour. This will help prevent the top from cracking. I did this, and did not have one crack on the top of my cake.
Cover and refrigerate until ready to serve. I removed the springform pan and decorated the top with Dulce de Leche and whole pecans a few hours before serving, then placed in the fridge until we were ready to eat.