Preheat the oven to 400* F.
Cream the butter and sugar together in a stand mixer or with a hand mixer until fluffy and well combined. Slowly add the flour, cinnamon and pinch of salt to the butter mixture while mixing.
Press the dough into a 9-inch by 13-inch baking dish so that the bottom is even and the dough comes up slightly onto the edges.
Bake the crust for 15 minutes until lightly browned.
While the crust is baking, add all of the filling ingredients to a large bowl and whisk them together until smooth.
Once the crust has finished baking, pour the pumpkin filling into the baking dish over the crust and bake for 40 to 45 minutes. The center should jiggle ever so slightly but not be liquid.
Let cool to room temp on the countertop and then chill in the refrigerator for 4 to 6 hours prior to cutting.
