For the crust:
 3/4 cup graham cracker crumbs
 1/2 cup finely chopped pecans
 1/4 cup firmly packed light brown sugar
 1/4 cup granulated sugar
 1/2 stick (1/4 cup) unsalted butter, melted and cooled
 For the filling:
 1 1/2 cups solid pack pumpkin
 3 large eggs
 1 1/2 teaspoons cinnamon
 1/2 teaspoon freshly grated nutmeg
 1/2 teaspoon ground ginger
 1/2 teaspoon salt
 1/2 cup firmly packed light brown sugar
 three 8-ounce packages cream cheese, cut into bits and softened
 1/2 cup granulated sugar
 2 tablespoons heavy cream
 1 tablespoon cornstarch
 1 teaspoon vanilla
 1 tablespoon bourbon liqueur or bourbon if desired
 For the topping:
 2 cups sour cream
 2 tablepoons granulated sugar
 1 tablespoon bourbon liqueur or bourbon, or to taste [and my taste says this is
not nearly enough]
 16 pecan halves for garnish
 Make the crust:  In a bowl combine the cracker crumbs, the pecans, and
 the sugars, stir in the butter, and press the mixture into the bottom
 and 1/2 inch up the side of a buttered 9-inch springform pan.  Chill
 the crust for 1 hour.
 Make the filling:  In a bowl whisk together the pumpkin, the eggs, the
 cinnamon, the nutmeg, the ginger, the salt, and the brown sugar.  In a
 large bowl with an electric mixer cream together the cream cheese and
 the granulated sugar, beat in the cream, the cornstarch, the vanilla,
 the bourbon liqueur, and the pumpkin mixture, and beat the filling
 until it is smooth.
 Pour the filling into the crust, bake the cheesecake in the middle of a
 preheated 350 degree F oven for 50 to 55 minutes, or until the center
 is just set, and let it cool in the pan on a rack for 5 minutes.
 Make the topping:  in a bowl whisk together the sour cream, the sugar
 and the bourbon liqueur.
 Spread the sour cream mixture over the top of the cheesecake and bake
 the cheesecake for 5 minutes more.  Let the cheesecake cool in the pan
 on a rack and chill it, covered, overnight.  Remove the side of the pan
 and garnish the top of the cheesecake with the pecans.