No one is certain who invented the whoopie pie; folks in both Pennsylvania Amish country and Maine have claimed it. As for the name, one theory is that it comes from children saying "whoopie!" upon finding the moist, chocolaty sweets in their lunch pails. Your kids can experience the same glee after baking their own -- and with pink-tinted filling, the pies will elicit cries of joy on Valentine's Day.
Make Scooping a Cinch: With a cookie scoop, young bakers can neatly make uniform drop cookies and cakes. The simple-to-use gadget works just like its ice-cream counterpart, enabling you to measure and drop dough with a squeeze of the handle. Many scoops form a cookie about the size of one made with a tablespoon, but scoops are also available in other sizes. You can find them at cooking supply stores (oxo.com offers a model similar to the one shown for $13).
Personalize the Whoopie Pies for Valentine's Day by wrapping them in large lollipop bags (available at craft stores) and attaching a message.
Heat the oven to 350°. Line two baking sheets with parchment paper.
In a medium bowl, whisk together the flour, cocoa powder, baking soda, and salt. In a glass measuring cup or small bowl, stir together the buttermilk and vanilla extract.
In a large bowl with a hand mixer set at medium speed, beat the butter and sugar until evenly blended, about 1 to 2 minutes. Add the egg, increase the speed to high, and beat until smooth and creamy, about 1 minute more.
Pour half the fl our mixture into the butter-sugar mixture, and beat at medium speed until combined. Add the buttermilk mixture and continue beating until just blended. Add the remaining fl our mixture and beat again.
Use a cookie scoop or spoon to place a heaping tablespoon of batter on a prepared cookie sheet. Add more mounds of batter, evenly spacing them, until there are nine on each sheet. Slightly fl atten each mound with a spoon.
Bake the cakes one sheet at a time for 10 minutes (they should be moist and spongy). Let them cool on the sheet for 2 minutes, then carefully transfer them to a rack to cool completely. Reline the sheets and scoop, shape, and bake the remaining batter.
Using an electric mixer at medium-high speed, beat all the fi lling ingredients except the coloring in a medium bowl until evenly blended, about 2 minutes. If you want to give the fi lling a Valentine hue, fold in drops of red food coloring until the desired tint is reached.
To make each pie, spoon and spread a heaping tablespoon of the filling onto the bottom of a cake, then gently press another cake on top.