Preheat the oven to 350 degrees F. and line a 8x10 inch or 9x9 inch pan with parchment paper.
In the bowl of a stand mixer, beat the butter and sugar.
Add the eggs and vanilla and combine.
Add the buttermilk and pumpkin puree and mix.
Add the flour, pumpkin spice, cinnamon, baking powder, baking soda, and salt and mix until just combined.
Pour into the prepared pan and bake for 30-40 minutes, until a toothpick inserted in the middle comes out clean.
Allow the cake to cool for about an hour, then remove it from the pan and let it cool completely on a wire rack.
Once cooled, transfer the cake to a large plate or dish and poke holes all over the surface of it.
Prepare the latte soak by melting the honey and milk together over low heat in a saucepan. Heat just until the honey is melted.
Remove from the stove and add the espresso and vanilla.
Pour the latte mixture over the cake and allow it to absorb. You may not need all of it.
Prepare the frosting by beating the cream cheese and butter until fluffy. Add the powdered sugar and pumpkin pie spice and beat.
Add the espresso powder to the vanilla extract and stir until it’s completely dissolved. Add this to the frosting and beat until combined.
Spread the frosting over the bars and cut them into squares.