1 - Preheat oven to 350 degrees. Line two baking sheets with Silpat baking mats or parchment paper, and set aside. In the bowl of an electric mixer fitted with the paddle attachment, combine sugars and butter; beat until light and fluffy, 3 to 4 minutes. Add eggs and vanilla, and beat on medium speed until well combined.
2 - In a large bowl, sift together flour, baking soda, baking powder, salt, cinnamon, nutmeg, and ginger; stir to combine. Gradually add flour to butter mixture; mix on a low speed until just blended. Mix in oats, carrots, and raisins. Chill dough in refrigerator until firm, at least 1 hour.
3 - Using a 1/2-ounce ice-cream scoop, scoop dough onto prepared baking sheets, leaving 2 inches between cookies. Transfer to oven, and bake until browned and crisped, rotating pan halfway through baking to ensure even color, 12 to 15 minutes. Transfer to a wire rack to cool. Repeat baking process with remaining dough. Once cooled completely, use an offset spatula to spread about 2 teaspoons of cream-cheese filling onto a cookie. Sandwich together with a second cookie. Repeat with remaining cookies. Store in an airtight container for up to 3 days in the refrigerator.
Cream Cheese Frosting
Place cream cheese in a medium mixing bowl. Using a rubber spatula, soften cream cheese. Gradually add butter, and continue beating until smooth and well blended. Sift in confectioners’ sugar, and continue beating until smooth. Add vanilla, and stir to combine.