By Julianne Dell, Beyond Frosting
For the cupcakes:
Preheat the oven to 350°F. Line a with cupcake liners. In a large mixing bowl, combine the sugar, vegetable oil, eggs and vanilla extract. Beat on medium speed until the eggs and oil are well incorporated and the batter is lighter in color, about 2 minutes. Scrape down the bowl as needed. Next mix in the sour cream and beat until well combined. Combine the dry ingredients in a separate bowl. Add half the dry ingredients followed by the half the milk and mix just until the flour starts to incorporate. Finally add the remaining dry ingredients and milk and beat until all of the ingredients are well combined.
Use a spatula to scrape down the sides of the bowl and stir the batter from the bottom to the top to ensure it’s well mixed. Using a large cookie scoop, divide the batter evenly, filling each liner 2/3 full. Careful not to overfill. Bake at 350°F for 14-16 minutes. Test the cupcakes for doneness by inserting a toothpick into the center of the cupcake. If the toothpick comes out clean, the cupcakes are done. Cool Completely.
For the frosting:
Cut the butter into pieces. Using the paddle attachment, whip the butter at medium high speed for 3-4 minutes, scraping down the bowl occasionally. Beat the butter until it looks lighter in color. Next add the peanut butter and incorporate into the butter, scraping the bowl as needed. Slowly add the powdered sugar, 2 cups at a time, adding the heavy cream and vanilla intermittently, mixing on low speed until it’s incorporated into the butter. Then increase the speed to high and beat for 30-60 seconds. Repeat until all your powdered sugar has been added. Lastly, add the marshmallow crème and beat until it’s well incorporated. Use a large piping bag fitted with a large open round piping tip to decorate these cupcakes.
For the filling:
Use a and take the top half of the center of your cupcakes out. Fill your piping bag with marshmallow crème and use the piping bag to fill the centers of the cupcakes. Pull the tops off those center pieces you previously removed and plop it back on top of the marshmallow filling.
For the topping:
Chop the peanuts into small pieces. Hold the cupcake in one hand and fill your other hand with peanuts. Gently press the peanuts into sides of the frosting. Store in an airtight container.