Preheat your oven to 350°F (175°C) and prepare a 9x13-inch baking pan by greasing or lining it with parchment paper.

In a large mixing bowl, whisk together the melted butter, granulated sugar, and brown sugar until well combined.

Add the eggs one at a time, mixing thoroughly after each addition, then stir in the vanilla extract.

In a separate bowl, sift together the flour, cocoa powder, ginger, cinnamon, nutmeg, and salt.

Gradually add the dry ingredients to the wet mixture, stirring until just combined; do not overmix.

Fold in the chocolate chips (if using) until evenly distributed throughout the batter.

Pour the batter into the prepared baking pan and spread it evenly.

Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted in the center comes out with moist crumbs.

Allow the brownies to cool in the pan before transferring to a wire rack for complete cooling.

Once cooled, cut into squares and serve, enjoying the festive flavors of gingerbread in a brownie form!