Peanut Butter Cream-Filled Devil's Food Cupcakes

INGREDIENTS

• 1 cup creamy peanut butter
• 1/2 cup buttermilk
• 1/2 cup (1 stick) unsalted butter, at room temperature
• 1 1/4 cups cake flour
• 1 1/2 cups granulated sugar
• 1/2 teaspoon salt
• 1 cup roasted peanuts, chopped
• 1/2 cup unsweetened Dutch- process cocoa powder
• 1/4 teaspoon baking powder
• 1/2 cup (1 stick) plus 2 tablespoons unsalted butter, at room temperature
• 1 teaspoon vanilla extract
• 1/2 cup hot strong coffee
• 1 1/4 cups sifted confectioners' sugar
• 1 teaspoon baking soda
• 4 ounces semisweet chocolate, roughly chopped
• 3 large eggs
• 1/2 cup heavy cream