Preheat your oven to 350°F (175°C) and prepare an 8x8 inch baking pan by greasing or lining it with parchment paper.

In a medium saucepan, combine 1/2 cup of unsalted butter, 1 cup of granulated sugar, and 1/3 cup of unsweetened cocoa powder. Stir over low heat until smooth and melted, about 5 minutes.

Remove from heat and let it cool slightly. Whisk in 2 large eggs, one at a time, until fully incorporated.

In a separate bowl, sift together 1 cup of all-purpose flour and a pinch of salt, then gradually fold into the chocolate batter until just combined.

Pour the batter into the prepared pan and bake for 25-30 minutes, until a toothpick inserted comes out with moist crumbs.

Allow brownies to cool in the pan for 10-15 minutes, then transfer to a wire rack to cool completely.

Melt 1 cup of white chocolate chips in a microwave-safe bowl in 30-second intervals, stirring until smooth. Optionally, mix in a drop of black gel food coloring.

Use a piping bag to drizzle the melted white chocolate over the brownies in a web pattern.

Let the decoration set for a few minutes before cutting into squares and serving.