Spray a 9” round pie dish or cake pan with cooking spray and set aside.

Add 4 ounces of marshmallows (about 16 marshmallows or 2 cups) and 1 ½ tablespoons of butter to a large microwave safe bowl. Microwave on high for 45 seconds then stir to combine. Microwave for an additional 30 seconds and stir until smooth and well combined. Stir in ½ teaspoon of vanilla.

Add 1 cup of rice krispies cereal and graham cracker crumbs to the marshmallow mixture and stir until well combined and uniformly coated.

Turn the mixture out into the prepared pie dish. Lightly spray your hands with cooking spray and press the mixture around the edge of the pan to create the crust. The crust should be approximately 1” thick. Set aside while you prepare the filling.

In another large microwave safe bowl add the remaining 6 ounces of marshmallows (about 24 marshmallows or 3 cups) and 2 ½ tablespoons of butter. Microwave on high for 60 seconds then stir. Microwave for another 30 seconds and stir until smooth. Stir in the remaining ½ teaspoon of vanilla, salt, food color and pumpkin pie spice until well combined.

Add the remaining 3 cups of rice krispies cereal to the marshmallow mixture and stir until well combined and evenly coated.

Turn the mixture out into the center of the prepared pie dish. Lightly spray your hands with cooking spray and press the mixture down to fill the center of the pie. Set the pie aside to set for at least 30 minutes to set before cutting into 8 slices and serving. Decorate with whipped cream if desired.