Whoopie pies are kind of a cross between a cookie and a cupcake. They are 2 soft cake-like cookies that delicately sandwich a frosting filling. You eat them with your hands like a cupcake or ice cream sandwich (or if you really want to, I guess you could use a fork).
I didn't really want a HUGE batch of cookies so I ended up making a half batch and it was plenty. I was a tiny bit short on peanut butter so it probably wasn't as peanut-buttery as the recipe intended. My peanut butter was also reduced sugar so I ended up adding a small amount of extra powdered sugar to make up for it. Delicious.
What I love most about whoopie pies is that the possibilities and combinations are endless! If you like this one, also give the Pumpkin Whoopie Pies a try! That one I personally loved even more than this (but I'm partial to those flavors more so than chocolate and PB :). That post also has a little more history on why they're supposedly called "whoopie pies" if you're curious.
Peanut Butter Whoopie Pies
Yields: About 20 fully assembled whoopie pies
For the pies:
- 3 1/2 cups all-purpose flour
- 1 1/2 cups unsweetened cocoa powder
- 1 tablespoon baking soda
- 1 teaspoon salt
- 2 sticks unsalted butter, room temperature
- 2 cups granulated sugar
- 2 large eggs
- 2 cups buttermilk, room temperature
- 2 teaspoons pure vanilla extract
- 1 1/3 cup creamy peanut butter
- 1 cup (2 sticks) unsalted butter, softened
- 1 1/2 cups confectioners’ sugar
- Salt, to taste
- Preheat the oven to 400 degrees Fahrenheit. Line baking sheets with parchment paper.
- Sift together flour, cocoa powder, baking soda, and salt into a small bowl; set aside.
- Put butter and sugar into a large mixing bowl. Cream together using an electric mixer high speed until smooth, about 3 minutes, until the mixture is pale and fluffy.. Add eggs, buttermilk, and vanilla and beat until well combined. On low speed, slowly add the flour mixture and mix until just combined.
- Using a small ice cream scoop or a large spoon, scoop rounded 1 1/2 tablespoons of dough onto baking sheets lined with parchment paper, spacing 2 inches apart. Bake until set, about 8 minutes. Let cool completely on wire racks. Repeat until all the cookie dough is used up.
- While cookies are baking and cooling, put peanut butter and butter in a bowl. Add confectioners’ sugar; mix with electric mixer on low until combined. Raise speed to high, and mix until fluffy and smooth, about 3 minutes. Season with salt, if desired.
- Spread a rounded tablespoon of filling on the bottom of 1 cookie. Sandwich with another cookie. Repeat with remaining cookies and filling. Cookies can be refrigerated in single layers in airtight containers up to 3 days. Bring to room temperature before serving.