Preheat oven to 350 degrees F. Spray an 8x8- inch baking dish with nonstick cooking spray; set aside.

In a large mixing bowl, combine flour, protein powder, baking powder, salt, Truvia and pumpkin pie spice. Add pumpkin puree, milk, melted butter substitute and vanilla; mix until just combined. Spread in an even layer in the bottom of prepared pan.

In a small bowl, mix together Truvia, chopped pecans and cinnamon then sprinkle on top of batter. Carefully pour hot water in an even layer over the top of the batter. DO NOT MIX (the batter will be submerged).

Place in the oven and bake for 35-40 minutes, or until golden brown on top. Let sit for 5 minutes then cut into slices and serve. Top with vanilla ice cream or Reddi Wip, if desired (log nutrition for toppings separately).