01 - Preheat oven to 350°F. Grease and flour a 9-inch square baking pan.
02 - In a large bowl, whisk together flour, ground ginger, cinnamon, cloves, nutmeg, baking soda, and salt.
03 - In a separate large bowl, beat butter and dark brown sugar until light and fluffy.
04 - Add eggs one at a time to the butter mixture, then stir in molasses and vanilla extract until fully combined.
05 - Add the dry ingredients to the wet mixture in three portions, alternating with the buttermilk, starting and finishing with the dry ingredients.
06 - Gradually stir in hot water until the batter is smooth and well blended.
07 - Pour batter into the prepared pan and level the surface.
08 - Bake for 32 to 38 minutes, or until a toothpick inserted into the center emerges clean.
09 - Allow cake to cool in the pan for 15 minutes, then invert onto a wire rack and cool completely.
10 - Serve plain, dust with powdered sugar, or accompany with whipped cream as desired.