Barefoot Contessa (en-US)

16 tablespoons (2 sticks) unsalted butter, at room temperature
2 cups plus 2 tablespoons all-purpose flour, divided
1 cup boiling water
5 ounces bittersweet chocolate, such as Lindt, roughly chopped
2 tablespoons unsweetened cocoa powder, such as Pernigotti
1 teaspoon instant coffee granules, such as Nescafé
1 teaspoon baking powder
1½ teaspoons kosher salt
1 cup roughly chopped walnuts
1 cup semisweet chocolate chips
1 cup granulated sugar
1 cup dark brown sugar, lightly packed
3 extra-large eggs, at room temperature
2 teaspoons pure vanilla extract

Preheat the oven to 350 degrees. Grease two (8½ × 4½ × 2½-inch) loaf pans, line the bottoms with parchment paper, then grease and flour the pans.

Pour the boiling water into a 2-cup glass measuring cup, add the bitter-sweet chocolate, cocoa powder, and coffee granules, and stir until the chocolate melts. Set aside to cool for at least 15 minutes.

In a medium bowl, sift together the 2 cups flour, the baking powder, and salt and set aside. In another bowl, combine the walnuts, chocolate chips, and the 2 tablespoons flour and set aside.

In the bowl of an electric mixer fitted with the paddle attachment, beat the butter, granulated sugar, and brown sugar together on medium speed for 2 minutes. With the mixer on low, add the eggs, one at a time, and then the vanilla, scraping down the bowl with a rubber spatula. Alternately in thirds, add the flour mixture and the chocolate mixture, beginning and ending with the flour. Fold in the nut mixture with a rubber spatula.

Divide the batter equally between the prepared pans, smooth the tops, and bake for 45 to 55 minutes, until a toothpick inserted in the middle comes out clean. (Test in a few places because you might hit a warm chocolate chip.) Cool in the pans for 30 minutes, turn out on a cooling rack, rounded side up, and allow to cool to room temperature.

Triple Chocolate Loaf Cakes