Unroll crescent roll dough in the bottom of the baking dish. Gently press with your fingers and push it about halfway up all the sides.
In the bowl of a stand mixer or a large mixing bowl, mix together all of the other ingredients: pumpkin puree, eggs, heavy cream, corn syrup, brown sugar, pumpkin pie spice and salt.
Pour the pumpkin pie filling over dough.
Bake on middle oven rack for about 45-55 minutes (or until the center is set.)
Allow to cool completely before slicing (at least a couple of hours.)
Once cooled, using the parchment paper hanging over the edges, lift it from the pan.
Garnish each bar with a dollop of whipped cream or sprinkle with some pumpkin pie spice.
To keep this simple, we are using crescent roll dough as the crust. Once it's all baked, it won't taste like crescent dough at all. The flavors blend with the filling so you won't taste it as a separate crescent dough flavor.
You can use refrigerated pie dough or even puff pastry dough as a substitute.
A 9x9 or 8x8 square baking dish may be substituted for the 11x7 baking dish. The bars will just come out a bit thicker.