Spray a 9x13 baking dish or plastic rectangular container with butter flavored non-stick spray. Set aside.
Cut the stick of butter into thirds. In a large sauce pan, melt one third of the butter over low heat. Stir in one third of the salt. Add one third of the marshmallows. Cook and stir constantly until the marshmallows are melted completely.
Remove from heat and stir in 4 cups of the cereal. Stir to combine well. Spoon into the prepared dish. Using a sheet of wax paper lightly coated with spray, press the layer of cereal mixture evenly.
Rinse the pot well. Repeat the process. During the marshmallow melting, stir in desired amount of orange food coloring. Stir completely until the color is even. Continue the process as before.
Rinse the pot and repeat the process, this time with yellow food color.
Allow the Candy Corn Rice Krispies to cool completely. Invert and cut into squares. Serve fresh or store in a tightly sealed container.