Ingredients:
- 1 ½ cups All-Purpose Flour
- 1 cup Granulated Sugar
- ½ cup Unsweetened Cocoa Powder (Dark/Dutch-Process)
- 1 teaspoon Baking Soda
- ½ teaspoon Salt (Fine Sea Salt)
- 2 Large Eggs, room temperature
- ½ cup Buttermilk, room temperature
- ¼ cup Vegetable Oil (Neutral)
- ½ cup Hot Water or Hot Coffee
- 1 teaspoon Pure Vanilla Extract
- ½ cup Creamy Peanut Butter (Full-fat, for filling)
- ¼ cup (4 Tbsp) Unsalted Butter, softened (for filling)
- ¾ cup Powdered Sugar, sifted (for filling)
- Pinch Salt (for filling)
- 1 cup (2 sticks) Unsalted Butter, softened (for frosting)
- 1 cup Creamy Peanut Butter (Full-fat, for frosting)
- 3 cups Powdered Sugar, sifted (for frosting)
- 2-4 Tablespoons Milk or Heavy Cream (Cold, for frosting)
- 1 teaspoon Pure Vanilla Extract (for frosting)
- ¼ teaspoon Salt (for frosting)
- 12 Miniature Reese’s Peanut Butter Cups (for garnish)
Instructions:
- Preheat oven to 350°F (175°C). Line the 12-cup muffin tin with paper cases.
- Make the Truffle Filling: In a small bowl, beat the softened butter and peanut butter until smooth. Gradually incorporate the sifted powdered sugar and salt until a stiff dough forms.
- Chill Truffle: Roll the filling into 12 small balls (approximately 1 tablespoon each). Place on a parchment-lined plate and chill in the fridge for at least 30 minutes to firm up.
- Combine Dry Ingredients: Whisk together the flour, granulated sugar, cocoa powder, baking soda, and salt in a large bowl.
- Combine Wet Ingredients: In a separate bowl, lightly whisk the eggs, buttermilk, oil, and vanilla extract until just combined.
- Mix Batter: Pour the wet mixture into the dry ingredients. Mix on low speed (or with a spatula) until just combined and there are no streaks of flour. Do not overmix.
- Add Hot Liquid: Carefully pour in the hot water or coffee. Mix briefly until the batter is smooth but thin.
- Bake: Fill the cupcake cases about two-thirds full. Bake for 18–20 minutes, or until a toothpick inserted into the centre comes out clean.
- Cool: Allow the cupcakes to cool in the tin for 5 minutes, then transfer them to a wire rack to cool completely (approximately 45 minutes). They must be fully cool before the next stage.
- Core the Cupcakes: Once cool, use a melon baller or corer to scoop a small conical piece from the centre of each cupcake, making a pocket for the filling.
- Stuff the Filling: Place one chilled peanut butter truffle ball into the pocket of each cored cupcake.
- Make the Frosting: In a stand mixer, beat the softened butter and peanut butter until light and creamy (2-3 minutes). Gradually add the sifted powdered sugar, alternating with the vanilla and milk/cream (start with 2 Tbsp milk). Beat on medium-high for 3-5 minutes until the frosting is light, fluffy, and pipeable.
- Decorate: Transfer the frosting to a piping bag fitted with your chosen tip. Pipe a generous swirl onto the top of each stuffed cupcake.
- Garnish: Place a mini Reese’s Cup on top of the frosting. Serve immediately or store.