Preheat your oven to 350°F (175°C). In a medium saucepan over low heat, melt the butter, mixing in the granulated sugar and brown sugar until smooth. Remove from heat and allow to cool slightly before whisking in eggs, one at a time, followed by vanilla extract.

In a separate bowl, sift together the all-purpose flour, cocoa powder, and salt. Gradually incorporate the dry mixture into the wet mixture, stirring gently until just combined.

Gently fold in the chocolate chips to the batter, being careful not to overwork it.

Pour the brownie batter into a parchment-lined baking pan, spreading it evenly. Bake for 30-35 minutes, or until a toothpick inserted in the center comes out with moist crumbs.

While the brownies cool, prepare the topping by combining chocolate chips with coconut oil in a microwave-safe bowl and heating until smooth.

Allow the brownies to cool completely. Spread the melted chocolate topping over the brownies, creating an even layer. Optionally, swirl in melted white chocolate colored with gel food coloring.

For perfect slices, warm a sharp knife under hot water, then wipe it dry. Carefully cut the brownies into squares.