In a medium-sized mixing bowl whisk together flour, baking powder, pumpkin pie spice, baking soda, and kosher salt, set aside.
In the bowl of an electric mixer add butter and beat until fluffy.
Add in dark brown sugar and mix until blended.
Add eggs, mixing thoroughly between each addition.
Mix in pumpkin puree.
Alternately add flour and buttermilk to the mixer batter.
Mix together until fully combined.
In your prepared pan add half the cake batter and top with little spoonfuls of half the cream cheese mixture.
Continue one more time and then swirl the batter to combine the cake and cream cheese mixture.
Top with streusel and bake for 45 minutes until the center of the cake is set and a toothpick comes out clean when tested in the center.
Let the cake cool and drizzle with glaze.