Preheat your oven to 350°F (180°C). Grease your loaf pan well and line it with parchment paper for easy removal.
Sift together the flour, cocoa powder, and salt into a large bowl. This ensures even distribution and prevents lumps.
In a separate bowl, cream the softened butter and sugar with an electric mixer until the mixture is light, fluffy, and pale—about 3-4 minutes. You should hear a gentle whir and see the mixture turn a soft, creamy color.
Add eggs one at a time, beating well after each addition. Watch for the mixture to become smooth and slightly thickened, with a shiny appearance.
Mix in the vanilla extract, then alternate adding the sifted dry ingredients and buttermilk in three and two additions respectively. Start and end with the dry ingredients, mixing just until combined after each addition. The batter will be thick but smooth.
Gently fold in the chocolate chips with a spatula, distributing them evenly throughout the batter without overmixing. This creates lovely pockets of melted chocolate in the final cake.
Pour the batter into the prepared loaf pan, smoothing the top with a spatula. Gently tap the pan on the counter to settle the batter and release any trapped air bubbles.
Bake for 55-60 minutes, or until a toothpick inserted into the center comes out with moist crumbs. The top should be slightly crackled and fragrant with cocoa aroma.
Remove the cake from the oven and let it cool in the pan for 15 minutes. Then, transfer it to a wire rack to cool completely, which helps set the crumb and makes slicing easier.
Once cooled, slice the cake with a serrated knife, revealing a moist, dense crumb with rich cocoa pockets. Serve as is or dust lightly with powdered sugar for a simple finish.
