1. 1. Prepare your baking pan: Preheat your oven to 350 F (175 C). Lightly grease and flour an 8×4-inch loaf pan, or line it with parchment paper for easy removal. This prevents sticking and ensures your bread comes out cleanly.

2. 2. Combine wet ingredients: In a large mixing bowl, whisk together the sourdough starter, granulated sugar, melted butter, egg, and vanilla extract until the mixture is smooth and well combined. The mixture should have a slightly creamy, uniform texture.

3. 3. Sift dry ingredients: In a separate medium bowl, whisk together the all-purpose flour, unsweetened cocoa powder, baking soda, and salt. Sifting ensures there are no lumps and helps distribute the leavening agents evenly.

4. 4. Combine wet and dry mixtures: Gradually add the dry ingredient mixture to the wet ingredients, mixing gently with a spatula or wooden spoon until just combined. Be careful not to overmix; a few streaks of flour are acceptable, as overmixing can lead to a tough bread.

5. 5. Fold in chocolate chips: Gently fold in the chocolate chips until they are evenly distributed throughout the batter. This is your chance to add a generous amount of chocolate goodness!

6. 6. Transfer to pan and bake: Pour the batter into your prepared loaf pan and spread it evenly. Place the pan in the preheated oven and bake for 25-30 minutes, or until a wooden skewer or toothpick inserted into the center of the bread comes out clean or with moist crumbs attached.

7. 7. Cool and serve: Once baked, remove the loaf from the oven and let it cool in the pan for about 10-15 minutes before carefully transferring it to a wire rack to cool completely. Slicing it while still warm is tempting, but a little cooling time helps it set and makes for cleaner slices.