Preheat your oven to 350°F (175°C). Thoroughly grease and flour a 10-inch bundt pan, making sure to reach all the nooks and crannies.
In a medium bowl, whisk together the flour, baking powder, baking soda, pumpkin pie spice, and salt until evenly distributed.
In a large mixing bowl, beat the butter and sugar on medium-high speed for 3-4 minutes until pale and fluffy.
Add eggs one at a time, beating well after each addition. Mix in the vanilla extract.
In a separate bowl, whisk together the pumpkin puree and cooled coffee until smooth.
Alternate adding the dry ingredient mixture and the pumpkin-coffee mixture to the butter mixture, beginning and ending with the dry ingredients (3 additions of dry, 2 of wet). Fold in the sour cream with the final addition.
Pour the batter into the prepared bundt pan and smooth the top. Bake for 55-60 minutes, or until a wooden skewer inserted in the center comes out clean with a few moist crumbs. If the top browns too quickly, tent loosely with aluminum foil after 40 minutes.
Allow the cake to cool in the pan for exactly 15 minutes. Then invert onto a wire rack to cool completely for at least 45 minutes before glazing.
For the glaze, whisk together powdered sugar, coffee, vanilla extract, and salt until smooth. Adjust consistency by adding more coffee (for thinner glaze) or powdered sugar (for thicker glaze) as needed.
Drizzle the glaze over the cooled cake, allowing it to cascade down the sides. While the glaze is still wet, sprinkle with the optional mixture of crushed graham crackers and pumpkin pie spice for a decorative finish.