Friends are good for a lot of things. Answering the phone when you need someone to talk to about your latest roommate troubles. Volunteering to drink a bottle of wine and “help” with your website. Enabling you to eat that pint of Ben & Jerry’s. Challenging you to make a creative peanut butter & jelly themed birthday treat…for the second year in a row.
And since our friendship was based on a mutual love of an obscure 1-hit wonder girl group (because how else do you know that your friendship is built to last?), I had to come up with something.
After some thought (and brain racking), I thought some peanut butter & jelly whoopie pies would do the trick. Peanut butter cake filled with peanut butter butter cream and jelly. It was just the kind of treat that my friend wanted.
So, turn up your girl power pop playlist and get to baking.
- for the cake
- 315 grams (2¼ cups) gluten-free all-purpose flour*
- 1 gram (1 teaspoon) xanthan gum**
- 10 grams (2 teaspoons) baking powder
- 5 grams (1 teaspoon) baking soda
- 3 grams (½ teaspoon) salt
- 205 grams (3/4 cup) smooth peanut butter
- 85 grams (6 tablespoons or ¾ stick) butter, softened
- 100 grams (½ cup) granulated sugar
- 110 grams (½ cup firmly packed) brown sugar
- 3 large eggs
- 1 cup + 2 tablespoons (265 ml) buttermilk
- for the filling
- 170 grams (1½ sticks) butter, softened
- 65-130 grams (1/4-½ cup) smooth peanut butter
- 675-900 grams (6-8 cups) confectioner’s sugar
- 2 teaspoons vanilla extract
- ½ cup (118 mls) milk
- pinch of salt
- ½ pint jar of your favorite jam or preserves
- Preheat oven to 350 degrees Fahrenheit (175 C). Position one rack in the center and one in the top third of the oven. Grease 2 whoopie pie pans.
- In a medium bowl, whisk together the flour, xanthan gum (if using), baking powder, baking soda and salt. Set aside.
- In the bowl of a stand mixer, cream together the peanut butter, butter, sugar and brown sugar for 3-5 minutes. You want the mixture to be light and fluffy.
- Add the eggs one at a time, beating for 1 minute on medium and scraping down the sides of the bowl before each addition.
- Add half the flour mixture and mix on low speed and slowly add the buttermilk.
- Scrape down the sides and add the rest of the flour mixture until the batter just starts to come together. Remove the bowl from the mixer and finish stirring with a spatula.
- Use a spring loaded ice cream scoop or spoon to add batter to each “well” of the pan.
- Bake for 12-15 minutes – they are done when they are golden brown and a toothpick comes out clean. Repeat with the remaining batter.
- In the bowl of a stand mixer combine the butter, 65 grams (1/4 cup) of the peanut butter, 450 grams (4 cups) of the sugar, the milk and the vanilla.
- Beat on medium for 3-5 minutes.
- Gradually add the remaining sugar 1 cup (115 grams) at a time, beating for 2 minutes after each addition.
- When the frosting is firm enough to pipe, stop adding sugar and add the salt. If the frosting is too firm or not peanut butter-y enough you can add more peanut butter. I used ¼ cup and nearly the full amount of powdered sugar. Your results will depend on the humidity, the type of peanut butter and how soft your butter was.
- Pipe a ring of frosting around the flat side of half the cakes, leaving the center empty.
- Fill the center with a dollop of jam and top with one of the cake pieces without frosting on it.