1 cup packed light-brown sugar
1 cup granulated sugar
1/2 pound (2 sticks) unsalted butter, room temperature
2 large eggs, room temperature
1 teaspoon pure vanilla extract
2 cups all-purpose flour
1 teaspoon baking soda
1 teaspoon baking powder
1/4 teaspoon salt
1 1/2 teaspoon pumpkin pie spice
2 cups old-fashioned rolled oats
1 1/2 cups finely grated carrots, (about 3 large carrots)
Preheat oven to 350 degrees. Line two baking sheets with Silpat baking mats or parchment paper, and set aside.
Combine sugars and butter; beat until light and fluffy, 3 to 4 minutes. Add eggs and vanilla, and beat at medium speed until well combined.
In a large bowl, sift together flour, baking soda, baking powder, salt, and pumpkin pie spice; stir to combine.
Gradually add flour to butter mixture; mix on a low speed until just blended.
Mix in oats and carrots. Chill dough in refrigerator until firm, at least 1 hour.
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, spread 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.