Heat oven to 350°F. Spray a 9x5-inch loaf pan with cooking spray.
In a small bowl, mix granulated sugar and 1 teaspoon of the pumpkin pie spice.
Separate dough into 8 biscuits. Separate each biscuit into 2 layers, making a total of 16 biscuit rounds.
Brush one side of each biscuit round with melted butter.
Spread slightly less than 1 tablespoon pumpkin pie mix on top of each. Sprinkle rounds with spice-sugar mixture.
Stack biscuits in 4 piles of 4 biscuits each. Place stacks on their sides in a row in the loaf pan, making sure sides without filling are on both ends touching the pan.
Bake for 40 to 45 minutes or until the loaf is deep golden brown and the center is baked through.
Cool for 10 minutes. Turn the pan upside down on the serving platter.
In a small bowl, mix powdered sugar, milk, vanilla and the remaining 1/4 teaspoon of pumpkin pie spice until thin enough to drizzle. Drizzle over warm loaf.
Serve warm.