Preheat oven to 350 degrees and line 2 cookie sheets with parchment paper. In a small bowl, stir together flour, baking powder, baking soda, pumpkin pie spice, and salt. Set aside.
In a large bowl, combine the oil, brown sugar, granulated sugar, egg, oats, carrots, and raisins. Slowly add in flour mixture and stir until combined.
Drop rounded tablespoons of dough two inches apart onto prepared cookie sheets. Bake each sheet for 12 minutes or until cookies begin to brown. Let stand 1 minute on cookie sheet, then remove to a wire rack to cool completely.
In a small bowl combine softened cream cheese, maple syrup, powdered sugar, vanilla, and pumpkin pie spice. Spread filling onto half of the cookies and top with remaining cookies to create sandwiches.