Preheat your oven to 350°F (177°C) and line a 9x9-inch baking pan with parchment paper.

In a mixing bowl, combine melted butter and brown sugar until smooth, then add eggs, molasses, and vanilla, mixing well.

In another bowl, whisk together flour, ground ginger, cinnamon, baking powder, and salt.

Gradually mix the dry ingredients into the wet mixture until just combined and spread evenly in the prepared pan.

Bake for 30-35 minutes, checking for doneness with a toothpick around the 30-minute mark.

Allow the brownies to cool completely in the pan, then lift out and dust with confectioners' sugar before slicing and serving.