First, preheat the oven to 350F. Butter and flour your Bundt pan very, VERY well, especially if it's one as intricate as the one I used!
In a large bowl, beat together the softened butter and brown sugar until light and fluffy. Add in the molasses, vanilla, and spices, and beat until well-incorporated.
Beat in the eggs, one at a time, until the mixture is smooth and creamy.
In a separate small bowl, whisk together the flour, baking powder, baking soda, and salt. Add in half of these dry ingredients into the wet mixture, and beat well. Add in all of the milk, followed by the other half of the dry ingredients.
Pour batter into prepared cake pan, and bake for 50-60 minutes, until the cake does not jiggle, and a toothpick inserted in the center comes out with just a few moist crumbs.
Let cake cool to room temperature, then flip out onto a plate and let it finish cooling. When ready to serve, sprinkle with powdered sugar and enjoy!