Preheat oven to 350°F. Lightly grease a 9-inch springform pan and line edges with two 3-inch high strips of parchment paper.
Combine graham crackers, sugar, cinnamon, and a pinch of salt in a medium bowl. Mix until combined. Pour in melted butter and stir until evenly moistened. Gently press mixture into the bottom and 1-inch up the sides of the prepared pan.
Bake crust for 12-15 minutes, or until set and lightly browned. Let cool completely.
Reduce oven temperature to 325°F and put a large roasting pan on the bottom rack. Fill a tea kettle with water and bring to a boil.
To make the filling, combine cream cheese, sugar, cornstarch, nutmeg, cinnamon and salt in the bowl of a stand mixer fitted with a paddle attachment. Beat on medium-low speed until soft and no lumps remain, scraping down bowl as needed. Mix in eggs and yolk, one at a time, until fully incorporated. Mix in the vanilla, sour cream, and eggnog until smooth and combined.
Pour batter into the prepared pan and gently tap to even out surface. Slide cheesecake onto the rack just above roasting pan, then fill roasting pan with boiling water. Bake for 1 hour 10 minutes, or until edges are puffed and middle jiggles like jello when you nudge it. Turn off oven and crack open the oven door for another hour to slowly cool.
Remove from the oven and cool another 30 minutes at room temperature. Chill for at least 3 hours in the refrigerator, preferably overnight. Unclamp springform ring and carefully peel off parchment paper.
Decorate with sugared rosemary and cranberries before serving.
