In a large bowl, whisk together the pumpkin puree, eggs, sugar, corn starch, pumpkin spice, cinnamon, salt, and vanilla extract. Then mix in the evaporated milk using a silicone spatula.
When the crust is done, reduce the temperature to 325 degrees and allow the crust to cool for 5 minutes.
Pour the pumpkin filling over the crust and bake for 60-65 minutes. To determine if the bars are done, the center should only slightly jiggle when shaken and the edges are completely set.
Allow the bars to cool at room temperature for 1 hour before placing them into the refrigerator for another 2-3 hours (I recommend 3 hours). Once completely cooled, slice into bars and then serve with whipped cream.
Keep any leftover pumpkin bars in an airtight container in the refrigerator for up to 4 days.