Into a small skillet over medium heat, add the chopped pecans in a single layer. Shake the skillet around a few times until the pecans are lightly toasted. Remove from the pan to cool.
For the egg replacer:
Into a small mixing bowl, whisk together VeganEgg powder and ice-cold water. Set aside.
If you are using a different brand of egg replacer, follow the package directions for baking with the equivalent of 3 eggs.
For the pumpkin pie filling:
Into a large mixing bowl, stir together the pumpkin puree, vegan evaporated milk, prepared egg replacer, granulated sugar, brown sugar, pumpkin pie spice, snd salt.
Pour into a prepared 9 x 13-inch baking dish.
For the cake topping:
Sprinkle the cake mix in an even layer to cover all of the pumpkin pie filling.
Sprinkle toasted pecans in an even layer over the cake mix.
Drizzle the entire top with melted butter.
Baking the cake:
Cover the cake with foil and bake for 45 minutes.
Remove the foil cover and continue baking for an additional 35 minutes.
Allow time for the cake to set:
Set the cake on a cooling rack and allow to cool completely.
Once the cake is completely cool, re-cover it with foil and set it in the refrigerator overnight or at least 2-3 hours to fully set.