Preheat oven to 350°. In a large bowl, combine cake mix, pudding mix, oil and 1 egg; mix until crumbly. Reserve 1 cup for topping. Press remaining mixture into an ungreased 13x9-in. baking pan. Bake 10 minutes. Cool completely on a wire rack., In a small bowl, beat cream cheese and sugar until smooth. Add remaining egg; beat on low speed just until combined. Fold in 1/2 cup toffee bits. Spread over crust. Sprinkle with reserved crumb mixture. Bake 15-20 minutes or until filling is set., Sprinkle with butterscotch chips and remaining toffee bits. Return to oven; bake 1 minute longer. Cool on a wire rack 1 hour. Refrigerate 2 hours or until cold. Cut into bars.