2teaspoonsvanilla extract or 1 teaspoon almond extract
4tablespoonsmilk or heavy cream
FOR THE TOPPING / DECORATION
2cupsmini marshmallows
½cupsemi sweet chocolate chips
½cupdry roasted peanuts
Instructions
FOR THE CUPCAKES
Heat the oven to 350 F. Line muffin pan with 20 paper liners.
In a 2-cup glass measuring cup, whisk together the cocoa powder and hot water until smooth, then set aside.
In a medium bowl, whisk together the flour, baking soda, baking powder, and salt. Set aside.
In a medium saucepan over medium heat, combine the butter and sugar, stirring occasionally until the butter is melted and the mixture is combined. Remove from the heat and transfer to the bowl of a stand mixer fitted with a paddle attachment. Beat on medium-low speed until the mixture is cool, about 4-5 minutes.
Add eggs and egg yolk, one at a time, beating until each is incorporated, scraping down the sides of the bowl as needed. Mix in vanilla extract and cocoa mixture until incorporated. With the mixer on low speed, add in the dry ingredients in two batches, alternating with the sour cream, beating just until combined.
Fill the cupcake papers three-quarters full. Bake for 18-20 minutes, rotating the pans after 10 minutes. Cupcakes are done when a toothpick comes out clean. Allow the cupcakes to cool for 5-10 minutes before transferring to a wire rack to cool completely.
FOR THE BUTTERCREAM:
Cream the butter for a few minutes on medium speed in a mixer with the paddle attachment on.
Turn off the mixer. Sift 3 cups powdered sugar and cocoa into the mixing bowl.
Turn your mixer on the lowest speed (so the dry ingredients do not blow everywhere) and mix until the sugar and cocoa are absorbed by the butter.
Increase mixer speed to medium and add vanilla extract, salt, and milk/cream and beat for 3 minutes. If your frosting needs a more stiff consistency, add a little more powdered sugar. If your frosting needs to be thinned out, add additional milk 1 tablespoon at a time.