Galatoire's Sweet Potato Cheesecake

This is a recipe from the NYT and R.W. Apple Jr.: https://cooking.nytimes.com/recipes/549-galatoires-sweet-potato-cheesecake?action=click&module=Local%20Search%20Recipe%20Card&pgType=search&rank=2

This recipe is adapted from a popular dessert served at Galatoire's, a famed New Orleans restaurant founded on Bourbon Street, in 1905. A simple graham cracker crust is filled with cinnamon-spiced sweet potato cheesecake then topped with a lightly-sweetened layer of sour cream. It is to die for. 

Ingredients

FOR THE CRUST:

• 1 ½ cups (180 g) graham cracker crumbs (from about 12 whole graham crackers)
• ¼ cup (50 g) sugar
• ⅓ cup (75 g) unsalted butter, melted

FOR THE CHEESECAKE FILLING:

• 1 (8-ounce / 225-g) package cream cheese, softened
• 1 cup (200 g) sugar
• ¼ cup (55 g) packed light brown sugar
• 1 ¾ cups (270 g) mashed sweet potatoes (see note)
• 2 large eggs, slightly beaten
• ⅔ cup (165 ml) evaporated milk
• 2 tablespoons cornstarch
• ¼ teaspoon ground cinnamon
• ⅛ teaspoon freshly ground nutmeg

FOR THE TOPPING:

• 2 cups (480 ml) sour cream, room temperature (1 16-ounce container)
• ⅓ cup (65 g) sugar
• 1 teaspoon vanilla extract  

 Preparation

1. Heat oven to 350 degrees. In a medium bowl, mix graham cracker crumbs, sugar and butter until combined. Press evenly onto bottom and 1 inch up side of a 9-inch springform pan. Bake until set but not brown, 6 to 8 minutes. Remove from oven, and cool.
2. Beat cream cheese with electric mixer until smooth. Add sugar and brown sugar, beating until completely smooth. Scrape down the sides of the bowl. Add sweet potatoes, eggs, evaporated milk, cornstarch, cinnamon and nutmeg, beating until well combined. Pour into crust. Bake until edge is set, 45 to 55 minutes.
3. Whisk sour cream, sugar and vanilla to combine. Spread over warm cheesecake. Return to oven, and bake until just set, 5 minutes. Cool completely on wire rack. Remove side of pan, and chill at least 5 hours and preferably overnight.

Tip

• For 1 ½ cups mashed sweet potatoes, you’ll need to roast 1 pound (455 g) sweet potatoes (about 2 medium sweet potatoes). Using a fork, pierce the potatoes in several places then roast in a 400°F oven until tender, 45 minutes to 1 hour. Once the sweet potatoes are cool enough to handle, cut them in half, scoop out the flesh, and mash until smooth.