Chocolate cupcakes with peanut butter

Ingredients:

Cupcakes

• 330 g unsalted butter, cut into pieces
• 1 cup cocoa powder
• 3 and 1/4 cups dark brown sugar
• 3 cups premium flour
• 1 teaspoon baking powder
• 0.5 tsp of soda
• 3/4 tsp salt
• 1 and 1/4 cups of sour milk or kefir
• 2 large eggs, room temperature
• 2 tsp vanilla extract

Grillage

• 0.5 cup granulated sugar
• 1/4 cup creamy peanut butter
• 1/4 cup toffee pieces

Glaze

• 1 cup heavy cream
• 2 packets of 280g granulated peanut butter

Preparation:

1. Position the oven rack on the middle shelf and preheat to 175°C (350°F) using the convection setting (if available). Line two 12-cup muffin tins with paper liners.
2. Bake cupcakes:
   
   In a medium microwave-safe bowl, combine the butter, cocoa powder, and 3/4 cup water. Cover with plastic wrap and microwave until the butter is melted, about 2 minutes. Stir, then add the brown sugar.
3. In a large bowl, combine the flour, baking powder, baking soda, and salt. Stir in the warm butter mixture. In another bowl, combine the buttermilk, eggs, and vanilla extract; fold into the batter to evenly distribute the ingredients, but do not overmix.
4. Divide the batter evenly among the prepared cupcake liners, filling each about three-quarters full. Bake until the cupcakes spring back when lightly pressed, 25-30 minutes. Cool in the pans for 10 minutes, then transfer to wire racks to cool completely.
5. Prepare the grillage:
   
   Line a baking sheet with a silicone mat or parchment paper. Pour granulated sugar into a small saucepan, bring to a boil over medium heat, and cook, swirling the pan but not stirring, until the caramel turns an amber color. Remove from heat.
6. Add the peanut butter and toffee and mix until smooth. Immediately pour the mixture onto the prepared baking sheet, spread it into a thin layer with a spatula, and let it cool. Break the candied nuts into pieces, place them in a zip-lock plastic bag, and crush them with a rolling pin.
7. Prepare the glaze:
   
   In a small saucepan, bring the cream to a simmer. Remove from heat, add the granulated peanut butter, and let sit for about 5 minutes. Stir until smooth.
8. Place the pan in a bowl of ice and chill, stirring occasionally, until the glaze thickens slightly, about 10 minutes.
9. Spread frosting onto muffins or transfer to a piping bag fitted with a large round tip and pipe onto muffins; sprinkle with nutmeg.