Sourdough Gingerbread

Preheat the oven to 350°F (175°C). Grease or line a 9 " x 9" metal baking pan (do not use a glass pan) generously with butter or parchment paper. Set aside.
Melt the butter in a microwave-safe bowl or a saucepan on the stovetop. Add the brown sugar to the melted butter and whisk until the sugar is dissolved, about 1-2 minutes.
Add the molasses and stir to combine. Add the egg and vanilla and stir to combine. Add the sourdough discard, and mix until fully combined.
Whisk the flour, baking soda, ground ginger, cinnamon, cloves, and salt in a medium mixing bowl.
Add the dry ingredients to the wet ingredients and fold together until completely combined.
Boil the water in a saucepan on the stove. Carefully stir the boiling water into the batter until the ingredients are fully combined.
Pour the batter into the baking pan and bake in the center rack for 40 minutes or until a toothpick inserted in the center comes out clean or with a few moist crumbs. Let it cool for 15-20 minutes and then turn out on a wire rack to cool completely before cutting.