Preheat your oven to 350°F (175°C) and line a 9×9-inch baking dish with parchment paper.

In a large mixing bowl, combine melted unsalted butter and light brown sugar, stirring until smooth and glossy.

Add room-temperature eggs, light molasses, and vanilla extract to the butter mixture, mixing until fully incorporated.

In another bowl, whisk together the all-purpose flour, ground ginger, ground cinnamon, baking powder, and kosher salt.

Gradually add the dry ingredients to the wet mixture, folding gently until just combined.

Pour the brownie batter into the lined baking dish, spreading evenly.

Bake for 30-35 minutes, checking for doneness by inserting a toothpick.

Allow brownies to cool completely in the pan, then dust with confectioners' sugar.