Preheat oven to 350 degrees
Beat cake mix together with water, pumpkin, and pumpkin spice oil
Line a 17 1/2 x 12 inch jelly roll pan with parchment paper and spray with cooking spray
Pour cake mixture into pan and bake 14-17 minutes until center is cooked, and no wobbly
Prepare a dish towel by sprinkling with powdered sugar on it
Place the hot cake on top of the towel, and peel off the parchment paper
Sprinkle the other side of the cake, and roll up in the towel to form a log
Meanwhile, use a hand mixer or blender to mix together your filling ingredients
When cake is cooled unroll it, remove it from dish towel, spread filling over it, and reroll
Make ganache by heating white chocolate chips in a microwave safe bowl for 30 seconds, then stir in cream and heat again (approx 20 second intervals) until chocolate is melted, then add in food coloring, stir well, and pour over cake roll to coat.
Cover and put in fridge for at least a couple hours, or freeze until ready to serve (plan to thaw 30 mins to an hour before serving).