Shaping Up Whoopie Pies

America s Test Kitchen

The Baseline

Made of two chocolate cookie-like cakes stuffed to the gills with a fluffy marshmallow filling, the whoopie pie is our idea of a good sandwich. Maine and Pennsylvania--the Pennsylvania Dutch of Lancaster County, to be specific--both claim whoopie pies as their own. While we weren't able to resolve the conflicting claims about the origins of the whoopie pie, the cream-cake-sandwich as we know it debuted in the 1920s.


Element of Distress

Pre-packaged whoopie pies--cellophane-packaged, mass-produced snack cakes--may be a modern convenience, but they are also wan, sickly sweet, and inferior to those made from scratch. And the original-original recipe surely needs a makeover: It calls for lard in the cake, plus a whipped frosting filling made of sugar and lard.


Line of Attack

We'd mix up a rightfully devilish whoopie pie with a new recipe that strikes the perfect balance of tradition in the modern kitchen.


ONWARD
Like many regional American classics, whoopie pie recipes haven't changed much over the years. Original recipes used a devil's food cake base, with "soda" and "soured milk" to lift the cakes. Which translates into--wait, wait, don't tell me!--baking soda and buttermilk. So we'd use them, naturally.

While the original cakes contained lard, many recipes have switched to shortening or vegetable oil, both of which extend the cakes' shelf life. Although it's considered heresy in the whoopie world, we used butter instead of shortening. You shouldn't have many concerns about shelf life--moist and tender, these cakes are so tasty that any risk of leftovers is nil.

Originally, the filling was a whipped frosting made of sugar and lard (there it goes again), but recipes soon switched to marshmallow crème, which was easily purchased under the name of Marshmallow Fluff.

Instead of mixing the marshmallow with lard or vegetable shortening, we turned once more to butter (there it goes again). We slathered this fluffy filling between two chocolate cookie-cakes and--whoopie!--there were the magical whoopie pies, right before our eyes.

As soon as you put these finished treats on your table, they'll be history in more than one way.

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Whoopie Pies

Serves 6

Don't be tempted to bake all the cakes on one baking sheet; the batter needs room to spread in the oven.

CAKES
2 cups all-purpose flour
½ cup Dutch-processed cocoa powder
1 teaspoon baking soda
½ teaspoon salt
1 cup packed light brown sugar
8 tablespoons (1 stick) unsalted butter, softened but still cool
1 large egg, room temperature
1 teaspoon vanilla extract
1 cup buttermilk

FILLING
12 tablespoons (1½ sticks) unsalted butter, softened but still cool
1¼ cups confectioners' sugar
1½ teaspoons vanilla extract
⅛ teaspoon salt
2½ cups Marshmallow Fluff

1. FOR THE CAKES: Adjust oven racks to upper-middle and lower-middle positions and heat oven to 350 degrees. Line 2 baking sheets with parchment paper. Whisk flour, cocoa powder, baking soda, and salt in medium bowl.

2. With electric mixer on medium speed, beat sugar and butter in large bowl until fluffy, about 4 minutes. Beat in egg until incorporated, scraping down sides of bowl as necessary, then beat in vanilla. Reduce speed to low and beat in one-third of flour mixture, then half of buttermilk. Repeat with half of remaining flour mixture, then remaining buttermilk, and finally remaining flour mixture. Using rubber spatula, give batter final stir.

3. Using ⅓-cup measure, scoop 6 mounds of batter onto each baking sheet, spacing mounds about 3 inches apart. Bake until cakes spring back when pressed, 15 to 18 minutes, switching and rotating pans halfway through baking. Cool completely on baking sheets, at least 1 hour.

4. For the filling: With electric mixer on medium speed, beat butter and sugar together until fluffy, about 2 minutes. Beat in vanilla and salt. Beat in Fluff until incorporated, about 2 minutes. Refrigerate filling until slightly firm, about 30 minutes. (Bowl can be wrapped and refrigerated for up to 2 days.)

5. Dollop ⅓ cup filling on center of flat side of 6 cakes. Top with flat side of remaining 6 cakes and gently press until filling spreads to edge of cake. Serve. (Whoopie pies can be refrigerated in air-tight container for up to 3 days.)

Browse more tempting chocolate desserts on Cook's Country.