Combine first 4 ingredients (mixture will be crumbly). Firmly press crumb mixture into bottom of a 9-inch springform pan coated with cooking spray. Bake at 350 degrees for 10 minutes; cool on a wire rack.
Combine pumpkin and next 4 ingredients (through cloves) in a bowl. Soften 6 cups ice crea; add to pumpkin mixture, stirring to blend. Spoon half of mixture into prepared pan. Cover with plastic wrap; freeze 1 hour or until firm. Cover and freeze remaining pumpkin ice cream.
Soften remaining 3 cups vanilla ice cream; stir in 3 tablespoons pecans. Spread over pumpkin ice cream layer; freeze 1 hour or until firm.
Soften remaining 3 cups pumpkin ice cream; spread over vanilla ice cream mixture. Cover; freeze 8 hours or until firm.
Cut torte into 12 wedges. Place 1 wedge on each of 12 plates. Place topping in a microwave safe bowl; microwave at High for 45 minutes. Top each serving with 1 tablespoon topping; sprinkle with 1/4 teaspoon pecans.