Pour melted chocolate in a small ziplock bag, then snip off the corner making a small hole. Pipe a little dollop of chocolate onto a Nutter Butter bite, then press a Hershey kiss on top to adhere. Repeat with the remaining Nutter Butters and Hershey kisses. Chill acorns in the freezer for about 2 minutes until chocolate has set.

Once set, pipe a tiny dollop of melted chocolate onto the Nutter Butter side of the acorn then immediately attach a mini chocolate chip; refrigerate until set.

Preheat oven to 350F degrees, and line a muffin pan with cupcake liners. Add the espresso powder to the hot water, and stir until fully dissolved; set aside.

In a large mixing bowl, whisk together the flour, cocoa powder, baking soda, salt, and both sugars until well combined. Add the oil and yogurt and continue stirring with a whisk. Batter will be thick so you'll have to add some of the espresso liquid to stir more easily. Add the rest of the espresso liquid and stir until combined. Stir in the egg, followed by the vanilla.

Pour batter into cupcake liners, filling 2/3 of the way. Bake in the oven for 16-18 minutes, or until a toothpick inserted in the center comes out with few crumbs attached. Allow cupcakes to cool in the pan for 5 minutes before transferring to a wire rack to cool completely.

In a stand mixer fitted with the paddle attachment, beat the butter and peanut butter together until smooth. Add vanilla extract, milk/cream, and 1 cup of the powdered sugar and continue mixing. Gradually add more powdered sugar, stirring between each addition, until you've reached the desired consistency. If frosting becomes too thick, add more milk/cream.

Pipe frosting onto cooled cupcakes as desired, then top with a Nutter Butter "acorn". Serve and enjoy!