Preheat oven to 350°F. Grease a 9x13 baking pan with cooking spray.
In a large mixing bowl, combine cake mix, sugar, oil, eggs, pumpkin puree, 2 teaspoons of pumpkin pie spice and vanilla. Beat with an electric mixer until smooth and combined. Pour batter into the prepared pan, smooth the top, and bake for 38-40 minutes, or until a toothpick comes out clean.
Let the cake cool for at least 30 minutes, then poke holes all over the cake with a bamboo skewer.
In a large bowl, combine evaporated milk, sweetened condensed milk, half and half and 1/2 teaspoon of pumpkin pie spice. Slowly pour over the cake, making sure to get in all the holes.
Top cake with plastic wrap and refrigerate for at least 6-8 hours (or until most of the milk has been absorbed).
Before serving, make the whipped topping. In a large bowl, whip cream with sugar (brown sugar works too) and vanilla with an electric mixer or a stand mixer. Mix until soft peaks form, then spoon and spread over the cake. Sprinkle with pumpkin spice or cinnamon before serving.