1. Prepare Your Baking Pan: Preheat your oven to 350 F (175 C). Lightly grease an 8×8 inch square baking pan with butter or cooking spray, then line it with parchment paper, leaving an overhang on two sides. This will make it much easier to lift the brownies out later.

2. Melt the Butter and Combine Sugars: In a large mixing bowl, melt the unsalted butter. You can do this in the microwave in 30-second intervals or on the stovetop. Once melted, stir in the granulated sugar until well combined. The mixture should look glossy.

3. Add Wet Ingredients: Whisk in the eggs one at a time, ensuring each is fully incorporated before adding the next. Stir in the vanilla extract and then the room-temperature sourdough discard. Mix until the batter is smooth and uniform.

4. Combine Dry Ingredients: In a separate medium bowl, whisk together the all-purpose flour, unsweetened cocoa powder, and salt. Make sure there are no lumps of cocoa powder.

5. Mix Wet and Dry: Gradually add the dry ingredient mixture to the wet ingredients, mixing until just combined. Be careful not to overmix, as this can lead to tougher brownies. A few streaks of flour are okay; they will disappear during baking.

6. Fold in Chocolate Chips: Gently fold in the chocolate chips. This ensures they are evenly distributed throughout the batter.

7. Bake the Brownies: Pour the batter into your prepared 8×8 inch pan and spread it evenly with a spatula. Bake for 25-30 minutes, or until a toothpick inserted into the center comes out with moist crumbs, but not wet batter. The edges should look set.

8. Cool Before Slicing: Remove the pan from the oven and let the brownies cool completely in the pan on a wire rack before lifting them out using the parchment paper overhang. This is crucial for fudgy brownies that hold their shape; cutting them warm can make them crumbly.