In a medium bowl, I whisk together the instant vanilla pudding mix, cold milk, pumpkin puree, pumpkin pie spice, and cinnamon. I mix until everything is smooth and slightly thickened. Then I set it aside to firm up while preparing the cream cheese layer.
In a separate large bowl, I beat the softened cream cheese and powdered sugar together using an electric mixer. I keep mixing until it’s creamy and completely smooth with no lumps. This step is important for creating a silky filling.
Next, I gently fold the pudding mixture into the cream cheese mixture until fully combined. Once blended, I carefully fold in the whipped topping using a spatula. I make sure not to overmix so the filling stays light and airy.
I spoon the pumpkin filling into the prepared graham cracker crust and spread it evenly with a spatula. I smooth out the top to make it look neat and inviting. At this point, it already smells amazing.
I place the pie in the refrigerator and let it chill for at least four hours. This allows the filling to firm up properly. When fully set, it slices beautifully and holds its shape.