For the cake

• 6 tablespoons unsalted butter, softened plus more for pan (see Note)
• 3 large eggs
• ¾ cup sugar
• ½ cup unbleached all-purpose flour
• 2 tablespoons cocoa powder
• 1 tablespoon finely ground espresso
• 1 teaspoon baking powder
• 1/8 teaspoon salt

For the filling:

• 1 cup (8 ounces) mascarpone cheese
• 1 tablespoon coffee-flavored liquor
• 1 tablespoon finely ground espresso

For the glaze:

• 5½ ounces semisweet chocolate, roughly chopped
• ½ cup heavy cream
• 1 tablespoon coffee-flavored liquor
• 1 tablespoon cocoa powder
• Whole coffee beans for garnish

To make the cake: Put rack in center position and heat oven to 350°. Butter an 8-inch cake pan. In the bowl of an electric mixer fitted with the whisk attachment, beat sugar and butter together at medium speed until pale and fluffy, about 3 minutes. Add eggs and beat 3 minutes more. In a bowl, whisk together flour, cocoa, espresso, baking powder and salt. Whisk dry ingredients into egg mixture. Pour batter into cake pan. Bake until edges darken and tester inserted into center comes out clean, about 30 minutes. Cool completely on wire rack, then remove from pan.

To make the filling: Place mascarpone, liquor and espresso in a bowl and stir well to combine. Using a serrated knife, cut cake in half widthwise. Transfer 1 layer, cut side up, to a cake plate. Spread mascarpone mixture over cake layer on plate. Place top half of cake over filling.

To make the glaze: Combine chocolate, heavy cream and liquor in a large metal bowl set over saucepan of barely simmering water. Stir until melted and combined, about 4 minutes. Pour glaze over cake, using a spatula to spread; let cake stand until glaze is set, about 30 minutes. Sprinkle with cocoa powder and coffee beans.

Note: When originally published in the magazine, the recipe did not include butter, and it tested well. But we found it was even better with the addition of butter.