This recipe is for Jenny, who is testing out recipes for her daughter's upcoming bat mitzvah. Let's get something straight right away: this isn't a cupcake designed for the adult tastebud. This cupcake is for kids. It tastes like a hostess cupcake, but better. This was one of my favorite recipes, growing up (and since my tastebuds haven't totally matured, I would still totally eat one of these today.) —Blissful Baker
Preheat oven to 350 degrees & place cupcake liners in a 12-cup muffin pan
In a separate bowl, whisk the flour & baking soda together and set aside.
In a glass measuring cup, blend the hot water & unsweetened cocoa powder and set aside.
In large mixing bowl, cream butter and sugar together until light & fluffy. Add egg and blend well. Add vanilla & sour cream and blend well. Turn mixer down to low speed & blend in the flour/baking soda mixture. Use a spatula to scrape down the sides of the bowl & slowly add the hot water cocoa mixture, blending until combined (about 1 more minute)
Pour into cupcake liners and bake for 20 minutes, until toothpick inserted in center comes out clean.
Allow to cool on cooling rack & prepare your filling:
In large mixing bowl, cream together the butter, fluff & powdered sugar.
Cut holes in the top of each cupcake, setting the little “caps” aside. Spoon filling into each hole & replace the caps.
Set cupcakes out and watch the kids devour them. Be sure and set one aside for your own inner child.