In a small bowl, whisk together the flour, baking powder, salt, and spices. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment (or with a hand mixer in a large bowl) beat together the butter and sugar until light and fluffy (~3-4 minutes).
Use a rubber spatula to scrape down the sides of the bowl. Add in the molasses, both eggs and the vanilla, then beat until well combined.
Add in half of the flour mixture, and mix by hand just until the flour is incorporated. Add in all of the espresso and buttermilk, and mix until combined. Add in the rest of the flour, and lightly fold the mixture together just until all of the flour is incorporated.
Pour the gingerbread latte cake batter into the prepared cake pan, smoothing out the top. Pour the streusel evenly over the top of the cake.
Bake for 40-45 minutes, until a toothpick inserted in the center of the cake comes out clean or with only a few moist crumbs. Let the cake cool in the pan until it’s no longer too hot to touch, then use the parchment paper to lift the cake out of the pan.