For Crust: Preheat oven to 350F. Finely chop nuts and sugar in processor. Add butter and blend, using on/off turns, until moist crumbs form. Using plastic wrap as aid, press mixture onto bottom and all the way up sides of 9-inch-diameter springform pan with 2 3/4-inch-high sides, covering completely. Freeze 10 minutes. Bake crust until golden, about 10 minutes. Cool. For Filling: Whisk 1 cup cream, sugar and yolks in heavy medium saucepan. Stir constantly over medium heat until candy thermometer registers 160 about 6 minutes. Strain into large bowl. Using electric mixer, beat mixture until cool and slightly thickened, about 8 minutes. Beat in pumpkin, corn syrup, rum and spices. Using electric mixer, beat remaining 1 1/2 cups cream in large bowl to medium-stiff peaks. Fold cream into pumpkin mixture. Transfer filling to crust. Cover and freeze overnight. For Topping: Arrange pecans side by side atop torte, covering completely. Drizzle 1/2 cup caramel sauce over, covering nuts completely (pan will be filled to top). Freeze until caramel sets, at least 3 hours or overnight. Run sharp knife around pan sides to loosen torte. Release pan sides. Stir remaining caramel sauce in heavy small saucepan over medium heat until warm. Slice torte and serve with sauce. Serves 12. Bon Appetit November 1994