First, preheat your oven to 350°F (175°C). This ensures it’s perfectly hot and ready to give your cake the perfect rise.

Grease a 9x5-inch loaf pan with butter or use non-stick spray. You can also line the bottom with parchment paper for an easy release after baking.

In a separate bowl, sift together the flour, cocoa powder, baking powder, and salt. This helps prevent clumps of dry ingredients in your batter and makes sure the cake rises evenly.

In a separate large bowl, beat the softened butter and cream cheese together. Use an electric mixer on medium speed for about 3-4 minutes until the mixture becomes light, fluffy, and smooth. This is the base for your cake's creamy texture.

Gradually mix in the granulated sugar and beat until it’s fully incorporated. Add the eggs one at a time, ensuring each one is fully mixed before adding the next. This helps the mixture stay smooth and airy.

Now, alternate between adding the dry ingredients and the sour cream to the wet mixture. Start with a third of the dry ingredients, followed by half of the sour cream, and continue alternating. Mix gently until just combined – be careful not to overmix, as this could result in a denser cake.

Slowly mix in the semisweet chocolate chips. This gives you pockets of melty chocolate in every slice. The folding motion helps keep the batter airy.

Transfer the batter into the prepared loaf pan and use a spatula to even out the surface. Place it in the oven and bake for 55-65 minutes, or until a toothpick inserted into the center comes out clean. If you find the top is browning too quickly, you can cover it loosely with foil.

Once your cake is baked, let it cool in the pan for 10 minutes. After that, remove it from the pan and transfer it to a wire rack to cool completely. This step is crucial to avoid the cake breaking apart when slicing.