Preheat the oven to 350°F (180°C) and butter and flour a 12-cup (2.8 liter) Bundt pan. Set aside.
In a separate medium bowl, combine the flour, pumpkin pie spice, baking powder, baking soda and salt, and then fold into the wet ingredients until evenly mixed.
Let the glaze cool until thickened but still pourable. Drizzle over the cake and let set before serving. Store in an airtight container at room temperature for up to 3 days.