Chocolate Whoopie Pies with Peanut Butter and Dulce de Leche Buttercream

Me and my little helper baked up the cookies this morning (which are good on their own by the way ), and then I hemmed and hawed the rest of the morning as to what filling to make. I had a few in mind, and then when I saw on twitter that it was National Peanut Butter day, it was an obvious choice that peanut butter had to be incorporated into the buttercream. But, this is no ordinary peanut butter buttercream, it’s light and fluffy and has dulce de leche in it! I mean, who doesn’t love dulce de leche? I absolutely love the combination of peanut butter and dulce de leche, it’s like they were meant to be.
This is a great simple cookie, it is soft and chocolatey, and the perfect backdrop to so many different flavoured fillings. The buttercream is light and fluffy, has a nice peanut butter flavour that’s not overwhelming, and has the caramel undertones from the dulce de leche.  Not only is this buttercream great on these whoopie pies, but perfect on cupcakes too!

Chocolate Whoopie Pies with Peanut Butter Dulce de Leche Buttercream
Makes about 10-12 sandwich cookies, depending on size

Cookies
1 3/4 cups all-purpose flour
1 teaspoon baking soda
1/4 cup unsweetened cocoa
1/4 teaspoon salt
1/2 cup unsalted butter, room temperature
3/4 cup granulated sugar
1 large egg
2 teaspoons vanilla extract
4 tablespoon plain yogurt or sour cream
3 tablespoons milk

1. Preheat oven to 350 degrees F, and adjust oven rack to middle position. Line 3 large cookie sheets with parchment or a Silpat.
2. In a small bowl, whisk together the flour, baking soda, cocoa powder, and salt. Set aside.
3. In the bowl of a stand mixer, beat the butter and sugar together until light and fluffy, about 5 minutes. Beat in the egg and then vanilla extract. Add in half of the flour mixture and mix just until combined. Add in the yogurt and milk, and mix until just combined. Mix in the remaining flour mixture until throughly combined.
4. Spoon or pipe the batter onto the prepared baking sheets, spaced about 2-3 inches apart as the cookies will spread. Bake, one sheet at a time, for about 10-12 minutes, until the cookies have risen and they are just firm to the touch. (They make take a little bit longer depending on how large you make them, but check by firmness). Let the cookies cool on the cookie sheet for 5 minutes, then transfer to a cooling rack to cool completely.

Buttercream
1/2 cup unsalted butter, room temperature
1/3 cup smooth peanut butter
1 1/2 cups confectioners sugar
1/8 teaspoon salt
1/3 cup dulce de leche
2 tablespoons heavy whipping cream

1. In the bowl of stand mixer fitted with the whisk attachment, beat the butter and peanut butter together until light, and well incorporated, about 3-5 minutes.
2. Add in the confectioners sugar, and beat until incorporated, about 2 minutes. Add in the salt and dulce de leche, and beat until well combined.  Add in the heavy cream and whip on high speed for about 5 minutes until light and fluffy.

Assembly
1. Spread or pipe the buttercream filling on the flat side of half the cookies, and top with a cookie about the same size.

Store in an airtight container, for up to 3 days.

Enjoy!

Jessica

Cookie adapted from Whoopie Pies by Angela Drake and buttercream portuguesegirlcooks original.