Spread pumpkin on a stack of paper towels and let it sit for about 5-10 to draw out moisture.
In a large saucepan melt butter over medium heat stirring frequently. Add pumpkin and continue heating and stir until well mixed.
Add in marshmallows and continue heating, stirring frequently until marshmallows are melted.
Add in pumpkin pie spice and stir in until evenly mixed. If a deeper orange color is desired add a few drops of orange food coloring.
Remove from heat and fold in rice krispies.
Evenly press mixture into prepared pan.
Allow to cool.
While the rice krispies mixture is cooling place white chocolate chips in a double boiler, or a heat safe bowl over a small pot of water. Heat over medium/high heat stirring frequently until melted and smooth.
Place in a piping bag and gently drizzle across rice Krispies treats.
Allow to cool before cutting. Cut into 9 squares and serve.
Store in an airtight container.
Notes
Add Candies: White chocolate chips inside or any other of your favorite treats.
Short cut tip: Use gel icing to decorate the top instead of melted chocolate, you can use all sorts of spooky colors