Whoopie pies are so fun - cakelike cookies sandwiched with a creamy filling. They are usually a few inches across, but this recipe makes much smaller cookies, about an inch across. Fun, bite-sized cookie sandwiches. This was originally a recipe for 
pumpkin whoopie pies, but I didn't use pumpkin. We had some banana squash that we purchased on clearance that needed to be used. So we cooked it in the slow cooker, then pureed it and used it in this recipe.
There is a very large variety of winter squash available - acorn squash, banana squash, hubbard squash, butternut squash - that can be used interchangeably in many recipes. We don't usually have pumpkin on hand, so it's nice to have alternatives when it comes to fall baking. The flavor and color will be different depending on what squash you use (my cookies are much more yellow than the original orange of pumpkin cookies), but they turn out equally delicious.
To prepare winter squash for use in baking, simply cut up the squash and remove the seeds, cook in either a slow cooker or the oven until it is soft, remove the skin, and mash the squash into a puree.
 Mini Winter Squash Whoopie Pies
Mini Winter Squash Whoopie Pies
Cookies:
2 cups all-purpose flour
1 teaspoon baking powder
1 teaspoon baking soda
1 teaspoon ground cinnamon
1/2 teaspoon ground ginger
1/2 teaspoon salt
1/2 cup butter, softened
1 1/4 cups granulated sugar
2 large eggs, at room temperature, lightly beaten
1 cup winter squash puree
1 teaspoon vanilla extract
Cream Cheese Filling:
4 ounces cream cheese, at room temperature
6 tablespoons butter, softened
1/2 teaspoon vanilla extract
1 1/2 cups powdered sugar
For cookies: Preheat oven to 350 degrees F. Lightly grease or line four baking sheets with parchment paper.
Combine flour, baking powder, baking soda, cinnamon,  ginger and salt in medium bowl. Beat butter and sugar in large mixer  bowl on medium speed for 2 minutes. Add eggs, one at a time, beating  well after each addition. Add squash and vanilla extract; beat until  smooth. Stir in flour mixture until combined. Drop by heaping measuring  teaspoons onto prepared baking sheets.
Bake for 10 to 13 minutes or until springy to the  touch. Cool on baking sheets for 5 minutes; remove to wire racks to cool  completely.
For cream cheese filling: Beat cream cheese, butter  and vanilla extract in small mixer bowl on medium speed until fluffy.  Gradually beat in powdered sugar until light and fluffy.
Spread a heaping teaspoon of filling onto flat side  of one cookie; top with flat side of second cookie to make a sandwich.  Repeat with remaining cookies and filling. Store in covered container in  refrigerator.