Whisk together first 3 ingredients in a large bowl; stir in milk and next 3 ingredients. Add bread cubes, stirring until moistened. Stir in butterscotch chips and pecans. Pour into a lightly greased 4-quart round slow cooker.
Cover and cook on LOW setting 2 hours or until center is set. Carefully remove slow cooker insert from heat element. Let stand, covered, 30 minutes. Serve pudding warm with whipped cream, if desired.