1. Preheat oven to 350 degrees F. Coat two baking sheets with cooking spray or line with parchment paper and set aside.
2. In a large mixing bowl, use an electric mixer on medium speed to mix brown sugar, oil, and 1 1/2 tsp. vanilla until well blended, about 3 minutes. Add eggs, one at a time, mixing until smooth after each egg. Add pumpkin and mix until incorporated.
3. In a separate bowl, stir together flour, baking powder, baking soda, salt, cinnamon, cloves, ginger, and nutmeg. Add half the flour mixture to the pumpkin mixture and mix on medium speed until smooth. Scrape down sides with a rubber spatula, and remaining flour mixture, and mix well.
4. Drop 2-Tbsp. portions of batter onto prepared baking sheets, leaving 2 inches between each portion to allow for spreading. Bake for 11 to 13 minutes, until puffed and set but still soft when touched lightly with fingertips. Let cakes cool for 3 minutes on baking sheets before transferring them to wire racks to finish cooling, about 15 to 20 minutes. Repeat with remaining batter.
5. Prepare filling while cakes are baking and cooling. In a large mixing bowl, use an electric mixer on medium speed to mix cream cheese and butter until creamy. Add 1 tsp. vanilla and half the confectioners' sugar; mix on low at first to combine, then on high until smooth. Add remaining confectioners' sugar and mix until smooth, about 3 to 4 minutes.
6. Assemble whoopie pies. Spoon filling onto the flat sides of half the cakes, dividing it evenly. Top with remaining cakes, flat side against the filling, rounded side up. Serve immediately, or wrap each whoopie pie individually in plastic wrap and store at room temperature for up to two days, or in freezer for up to two months.
Source: Hannaford Fresh Magazine, July - August 2008