Preheat oven to 375F. Line a jelly roll pan (15 x 10'') with parchment paper, leaving an extra inch of parchment on both long sides of the pan. Spray parchment paper with non-stick cooking spray.

In a large bowl, whisk together flour, salt, baking soda, cinnamon and pumpkin pie spice. In a separate bowl mix the eggs, sugar, vanilla and pumpkin until smooth. Add dry ingredients to the bowl and stir just until combined and no dry streaks remain. Spread the batter evenly in the prepared pan. Sprinkle the walnuts, if using, on top of the mixture. Bake 14-15 minutes until a toothpick inserted in the center comes out clean.

While the cake roll is cooling, mix Cream Cheese Filling together with an electric mixer until fluffy and smooth. 

Once cake roll is cooled completely, unroll it very carefully. Gently smooth filling in an even layer over cake. Remove parchment paper and gently roll up cake. Cover with plastic wrap and refrigerate for at least 1 hour before serving.

Dust top with powdered sugar, if desired. Cut into slices and serve. Store in fridge, covered, for up to three days.