Crust
1 1/2 cups graham cracker crumbs
1/3 cup butter or margarine, melted
1/4 cup granulated sugar

Combine graham cracker crumbs, sugar and butter in medium bowl. Press onto bottom and 1 inch up side of a 9-inch springform pan. Bake at 350 degrees F for 6 to 8 minutes. Do not allow to brown. Remove from oven; cool.

Cheesecake
24 ounces cream cheese, softened
1 cup granulated sugar
1/4 cup packed brown sugar
1 3/4 cups solid pack pumpkin
2 eggs
2/3 cup evaporated milk
2 tablespoons cornstarch
1 1/4 teaspoons ground cinnamon
1/2 teaspoon ground nutmeg

Beat cream cheese and sugars in large mixer bowl until fluffy. Beat in pumpkin, eggs and evaporated milk. Add cornstarch, cinnamon and nutmeg; beat well. Pour into crust. Bake at 350 degrees F for 55 to 60 minutes or until edge is set but center still moves slightly.

Topping
1 (16 ounce) container sour cream,
    (at room temperature)
1/4 to 1/3 cup granulated sugar
1 teaspoon vanilla extract

Combine sour cream, sugar and vanilla extract in small bowl. Spread over surface of warm cheesecake. Bake at 350 degrees F for 8 minutes. Cool on wire rack. Chill for several hours or overnight;

To serve, run a knife around inside edge of pan. Remove pan sides. Place cake on a serving plate. Garnish with caramelized pecan halves, if desired.

NOTE: To caramelize pecans, arrange 20 pecans halves 1 inch apart on a foil-lined cookie sheet. Cook 1/2 cup sugar in a small saucepan over medium-low heat, stirring occasionally, until melted and dark amber in color. Slowly pour over pecans. Let cool until hard. Break apart.