Preheat Oven to 350° and spray a 9 x 13 pan with cooking spray.
Using a large bowl, whisk together the flour, ground ginger, ground cinnamon, baking soda, kosher salt, ground cloves, ground nutmeg, and light brown sugar.
Using a large saucepan, combine the butter, water and molasses over medium heat until the butter is melted.
Bring the mixture to a boil.
Gradually whisk in the dry ingredients into the saucepan.
Remove from the stove and allow to cool for a few minutes
Whisk in the buttermilk, eggs and vanilla until combined
Pour the batter into the baking dish and place onto a cookie sheet
Bake in the oven for 20-25 minutes or until a toothpick comes out clean
Allow to cool
Using a standing mixer, beat together the cream cheese, butter, powdered sugar, vanilla, heavy whipping cream and 1 tbsp ground cinnamon until combined and smooth
Spread evenly over the top of the cake and sprinkle some more cinnamon on top