Lightly spoon flour into a dry measuring cup; level with a knife. Combine flour, cocoa, and salt in a medium bowl, stirring with a whisk; set aside. Combine sugar, milk, vanilla, and egg in a medium bowl, stirring with a whisk until well combined; set aside.
Place butter and chocolate chips in a small microwave-safe bowl. Microwave at high 1 minute or until butter and chocolate melt, stirring every 20 seconds. Add chocolate mixture to sugar mixture, stirring with a whisk. Fold in flour mixture. Spread batter into a 9-inch deep-dish pie plate coated with cooking spray. Bake at 350° for 15 minutes or until a toothpick inserted in center comes out clean. Cool completely on a wire rack.
To prepare filling, place softened ice cream in a large bowl; beat with a mixer at medium speed until smooth. Spoon half of ice cream over cooled crust, and place remaining ice cream in refrigerator. Drizzle pie with 1/3 cup caramel. Freeze pie for 30 minutes or until firm. Spread the remaining ice cream over caramel. Sprinkle evenly with pecans; drizzle with 3 tablespoons of caramel. Cover and freeze 4 hours or until firm.