Preheat the oven to 350℉. Grease an 8x8" pan with cooking spray and line with parchment paper.
In a large bowl, whisk together the cooled, melted butter, brown sugar, and molasses. Add eggs and whisk until thoroughly combined. This will take a few minutes. Mix in the salt and vanilla.
1 stick butter, melted and slightly cooled, 1 cup packed brown sugar, ¼ cup molasses, 2 large eggs, ¾ teaspoon salt, 1 teaspoon pure vanilla extract
Using a fine mesh strainer or sifter, sift the flour, baking powder, cinnamon, ginger, cloves, and nutmeg into the egg mixture and fold to combine.
1 cup flour, ½ teaspoon baking powder, 1 teaspoon ground cinnamon, 1 teaspoon ground ginger, ¼ teaspoon ground cloves, ¼ teaspoon ground nutmeg
Pour the batter into the prepared baking pan and bake until set, about 20 to 25 minutes. Let cool completely.
Using the parchment, lift the gingerbread out of the pan and place it on a cutting board. Cut into 9 squares and dust with powdered sugar before serving.
2 tablespoons powdered sugar, for dusting