Preheat oven to 350℉ (180℃)
Grease two 6" round baking pans or line bottoms with parchment paper.
Sift together flour, ginger, cinnamon, nutmeg and baking soda. Set aside.
2 Cups All Purpose flour, 2 teaspoons Ground ginger, ½ teaspoon Ground cinnamon, ¼ teaspoon Ground nutmeg, 1 teaspoon Baking soda
Whisk together hot water and molasses until well combined. Set aside.
¾ Cup Hot water, ¾ Cup Molasses
Place brown sugar and softened butter in the bowl of a stand mixer (note: a hand mixer may also be used). Using the paddle attachment, begin mixing together butter and sugar until well combined (approximately 2 minutes)
⅓ Cup Brown sugar, ½ Cup Unsalted butter
Add egg to mixing bowl. Mix on medium speed until well combined.
1 Large Egg
Add ⅓ of the dry ingredients (flour, baking soda and spices) to mixing bowl. Mix on low speed until just combined.
Add half of the molasses/water. Mix on low speed until combined.
Add the second ⅓ of dry ingredients to mixing bowl. Mix on low speed until combined.
Add remaining molasses/water. Mix on low speed until combined.
Add remaining dry ingredients. Mix on low speed until combined.
Divide batter evenly between cake pans.
Bake for 25 - 30 minutes. Cake will be well risen and a toothpick inserted into the center will come out clean.
Remove cake from oven and place on a wire rack to cool completely. Unmold from cake pans once cooled.
Slice the dome off of both cakes and discard (or use for cake pops, snacking on, etc...). Then, slice each cake in half to create a total of four layers.