1 3/4 cups finely crushed graham cracker crumbs
1/3 cup butter, melted
1/4 cup granulated sugar
1/4 cup finely chopped pecans
1 2/3 cups butterscotch chips - divided use
1 (14-ounce) can sweetened condensed milk
4 (8-ounce) packages cream cheese, softened
1/2 cup granulated sugar
1/4 cup all-purpose flour
2 teaspoons vanilla extract
4 large eggs, slightly beaten
Whipped cream and caramel sauce for garnish (optional)
Preheat oven to 325°F (160°C). Wrap outside bottom and side of 9-inch springform pan with double layer of heavy-duty foil; set aside.
To make the crust, combine graham cracker crumbs, butter, granulated sugar and nuts in medium bowl. Press crumb mixture onto bottom and 1-inch up side of prepared pan. Set aside.
Remove 2 tablespoons of morsels and set aside for garnish. Combine milk and remaining morsels in medium saucepan and cook over low heat until morsels are melted and mixture is smooth; remove from heat. Cool to room temperature.
Beat cream cheese, granulated sugar, flour and vanilla extract in large mixer bowl until combined. Add butterscotch mixture; beat until smooth. Add eggs, beat just until combined. Pour into prepared pan. Place pan in large roasting pan; fill roasting pan with warm water half way up side of spring-form pan.
Bake for 1 1/4 to 1 1/2 hours or until 2 1/2-inch area around outside edge appears set when gently shaken. Carefully remove cheesecake from water. Pull foil away from pan and lift spring-form pan out of foil to wire rack. Cool on wire rack for 15 minutes. Run knife around edge of cheesecake. Cover; refrigerate for 6 hours or overnight to set completely.
Remove side of pan and place the cheese cake on a cake rack or serving platter. Top a slice of cheesecake with whipped cream, drizzle with caramel sauce and sprinkle with reserved morsels, if desired.