Preheat the oven to 350°F. Prepare a 9x13 inch baking pan by spraying the sides with a cooking spray (Baker's Joy is my favorite) and fitting the bottom with parchment paper. Alternatively, you can grease and lightly flour the pan.
Add the flour, baking powder, baking soda, salt, ginger, cinnamon, nutmeg, and cloves into a bowl. Whisk to combine and set aside.
In the bowl of your stand mixer (a handheld mixer works fine too!), cream the butter on medium-high for two minutes. Add in the white and brown sugars and cream on medium-high for another two minutes until light and fluffy, scraping down the bowl and paddle as needed. Turn the mixer to low and add the eggs one at a time. Add the vanilla and molasses, turn the mixer to high, and beat for one full minute.
With the mixer on low speed, alternate adding the flour mixture and the buttermilk, beginning and ending with the flour mixture. Mix until just incorporated. Scrape down the sides and bottom of the bowl and give it a few stirs to make sure there are no lumps. Batter will be thick, but pourable.
Pour the batter into the prepared cake pan and bake for 28-32 minutes, until it springs back to the touch and a toothpick inserted into the middle comes out with just a few moist crumbs. Let the cake cool to room temperature before applying any frosting.