Is it a pie? Is it a cake? Or is it a cookie? It must be a whoopie pie! These chocolaty, cakelike cookies sandwich a gooey sweet and salty caramel. The result is a decadent dessert that is positively addictive. Dulce de leche is a thick caramel sauce made from evaporated milk that is slowly simmered for a long time. It’s available at most Latin grocery stores and many upscale grocers.
Whoopie Pies with Salted Dulce de Leche
For the cookies:
6 Tbs. (3 oz./90 g) unsalted butter, at room temperature
1/2 cup (3 1/2 oz./105 g) firmly packed light brown sugar
1 tsp. vanilla extract
3/4 cup (4 oz./125 g) all-purpose flour
1/2 cup (1 1/2 oz./45 g) natural cocoa powder
1/2 tsp. baking soda
1/4 tsp. kosher salt
For the filling:
4 Tbs. (2 oz./60 g) unsalted butter, at room temperature
3/4 cup (3 oz./90 g) confectioners’ sugar
2 Tbs. heavy cream
1/4 to 1/2 tsp. kosher salt
1/3 cup (3 fl. oz./80 ml) dulce de leche
To make the cookies, in the bowl of a mixer fitted with the paddle attachment, beat the butter and sugar on medium-high speed until combined. Add the egg and vanilla and beat until blended. Sift the flour,
cocoa, baking soda and salt into the bowl and beat just until blended. Cover the bowl and refrigerate the dough until firm, about 2 hours.
Space 2 racks evenly in the oven and preheat to 350°F (180°C). Line 2 baking sheets with parchment.
With dampened hands, shape tablespoonfuls of the dough into balls. Place them firmly on the prepared pans, spacing them slightly apart and squishing them a little. You should have about 20 balls. Bake until the cookies are puffed and slightly firm, 8 to 10 minutes, rotating the pans about halfway through. Let the cookies cool on the pans for 5 minutes, then transfer to wire racks to cool completely.
While the cookies are cooling, make the filling: In the bowl of a mixer fitted with the paddle attachment, beat the butter and confectioners’ sugar on medium-high speed until lightened. Stir in the cream and salt, to taste, on low speed, then stir in the dulce de leche until the filling is smooth.
Spread the flat side of half of the cookies with a big dollop of the filling. Top each with a second cookie, placing the flat side on the filling. (You’ll probably have a bit more filling than you need, but this means you can sneak spoonfuls here and there.) Refrigerate until the filling is set, at least 1 hour. Makes 10 whoopie pies.