Chocolate Pecan Ice Cream Torte

1 jar (12 1/4 ounces) caramel ice cream topping
2 milk chocolate candy bars, chopped
12 pecan shortbread cookies, crushed
3 Tbsp butter, melted
1 cup pecan halves, toasted, divided
1/2 gallon butter pecan ice cream, slightly softened
1/2 gallon chocolate ice cream, slightly softened

In a microwave-safe bowl, combine the caramel topping and candy bars. Microwave, uncovered, on high for 1 1/2 minutes or until candy bars are melted, stirring every 30 seconds. Cool.
In a small bowl, combine the shortbread cookie crumbs and butter. Press onto the bottom of a greased 10  inch springform pan. Chop 1/2 cup pecans; set aside. Spoon half of the butter pecan ice cream over the crust. Drizzle with 2 tablespoons caramel sauce; sprinkle with 1/4 cup chopped pecans.
Spread half of the chocolate ice cream over top. Drizzle with 2 tablespoons of the caramel sauce; sprinkle with remaining chopped pecans. Spoon remaining butter pecan ice cream around the edge of the pan; spread remaining chocolate ice cream in the center of the pan. Cover and freeze overnight.
Carefully run a knife around edge of pan to loosen; remove sides of pan. Top with remaining pecan halves; drizzle with 2 tablespoons caramel sauce. Serve with remaining caramel sauce.