Begin by preheating the oven to 350°F/175°C. Generously grease your pound cake pan or bundt pan with baking spray or butter and a dusting of flour.
Combine 2 cups all-purpose flour, 2 cups sugar, 3/4 cup baking cocoa, 1 1/2 tsp baking soda, and 1 tsp of salt in a large bowl. Whisk together until combined, then set aside.
In a separate large bowl, add 1 tsp instant espresso or instant coffee into 1 cup of warm water and stir until dissolved. You can also use 1 cup of strong brewed coffee in place of the hot water / instant coffee mixture.
Add 1/2 cup buttermilk, 1/2 cup sour cream, 1 cup melted butter, and 2 tsp vanilla extract into the instant espresso mixture. Whisk together until the ingredients are combined. Then mix in 2 large eggs.
Pour the dry ingredients into the wet ingredients. Whisk together until smooth. Scrape the sides and bottom of the bowl as needed with a rubber spatula. If desired, fold 1/2 cup of mini chocolate chips into the batter with a rubber spatula.
Pour the batter into the prepared pan. Bake for 45-55 minutes, or until a toothpick inserted into the center of the cake comes out with a few moist crumbs.
Remove from the oven and let the cake sit in the pan for about 15 minutes. Carefully invert the pan onto a wire rack to remove the cake from the pan. Let the cake finish cooling there.