Classic Brownies

Instructions

1. Prepare the baking pan
   Preheat your oven to 350°F (175°C). Line a 9x13 inch baking pan with parchment paper, leaving an overhang on the sides to lift the finished brownies out easily. Lightly grease the parchment paper.
2. Melt the butter and chocolate
   In a large microwave-safe bowl, melt the butter in 30-second intervals. Once melted, whisk in the sugar until well combined. Allow the mixture to cool slightly.
3. Add wet ingredients
   Whisk the eggs into the butter-sugar mixture one at a time, ensuring each is fully incorporated before adding the next. Stir in the vanilla extract until the mixture is smooth and glossy.
4. Incorporate dry ingredients
   Sift the cocoa powder, flour, and salt into the wet ingredients. Add espresso powder if using. Gently fold with a rubber spatula until just combined, being careful not to overmix.
5. Add mix-ins
   Fold in the chocolate chips and walnuts (if using) until evenly distributed throughout the batter.
6. Bake the brownies
   Pour the batter into the prepared baking pan, spreading it evenly into the corners. Bake for 25-30 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs (not wet batter).
7. Cool completely
   Allow the brownies to cool completely in the pan on a wire rack for at least 1 hour. The cooling time is crucial for the brownies to set properly and develop their fudgy texture.
8. Cut and serve
   Once cooled, lift the brownies out of the pan using the parchment paper overhang. Place on a cutting board and cut into 16 equal squares with a sharp knife. Clean the knife between cuts for neat edges.