Instructions

• Preheat oven to 350°F. Line muffin tins with paper liners and set aside.
• In the bowl of a stand mixer (or a large mixing bowl), combine 2 cups granulated sugar, 1 3/4 cups all-purpose flour, 3/4 cup Dutch-processed cocoa, 1 1/2 teaspoons baking powder, 1 1/2 teaspoons baking soda, and 1 teaspoon salt. Stir briefly to blend.
• Add 2 large eggs, 1 cup whole milk, 1/2 cup canola or vegetable oil, and 2 teaspoons vanilla extract. Beat on medium speed for 1 minute, until the batter is smooth.
• With the mixer running on low, slowly pour in 1 cup boiling water and mix just until smooth. The batter will be thin — that is normal. Do not overmix.
• Fill each lined muffin cup about 1/2 full with batter. Bake 18–22 minutes, or until a toothpick inserted into the center of a cupcake comes out clean.
• Remove cupcakes from the oven and transfer to a wire rack. Cool completely before frosting.
• While the cupcakes cool, melt and cool the chocolate for the buttercream: melt 1 cup semi-sweet chocolate chips until smooth (microwave in short 20–30 second bursts, stirring between, or melt over a double boiler). Set the melted chocolate aside to cool to room temperature.
• Make the chocolate buttercream: in the bowl of a stand mixer, beat 1 cup unsalted butter (room temperature) on medium speed until light and fluffy, about 2–3 minutes. Gradually add 2 cups powdered sugar and mix until smooth, about 3–4 minutes. Mix in 1 teaspoon vanilla extract. Drizzle in the cooled melted semi-sweet chocolate and beat on medium speed until the frosting is smooth and creamy. Transfer the frosting to a pastry bag fitted with your preferred tip (or use a spatula).
• Make the ganache: place the remaining 1 cup semi-sweet chocolate chips in a medium bowl. Heat 1/2 cup heavy cream in a small saucepan over medium heat until it just begins to bubble around the edges (or heat in the microwave). Pour the hot cream over the chocolate chips, let stand 30 seconds, then stir until the chocolate is fully melted and the ganache is smooth, about 1–2 minutes. Let the ganache cool slightly so it is warm but pourable.
• Assemble the cupcakes: when cupcakes are completely cool, spoon a small amount of ganache onto the center of each cupcake and spread gently toward the edges to create a thin ganache layer. Let the ganache set for about 5 minutes.
• Pipe the chocolate buttercream over the ganache on each cupcake. If desired, decorate with 1 1/2 cups mini chocolate chips.
• (Optional) If you plan to pipe very tall swirls of frosting, you may need more frosting than this recipe yields; consider making extra if you want higher swirls.