In a food processor, combine the flour, butter, and salt, and pulse until the mixture is very coarse. Pour the flour/butter into a large bowl and add the ice water. Pour out onto a clean, flat surface into a large log. Using the palm of your hand, gently push and pull the mixture to form it into a dough.
Do not knead, you are just slightly manipulating it. Form into a disc and wrap. Chill. Roll out on floured surface and place in greased 9-inch tart pan. Blind bake tart shell for 10 minutes in a 350 degree F oven.
In a mixing bowl, combine sweet potato puree, eggs, sugar, orange juice, heavy cream, butter, and spiced thoroughly. Pour sweet potato mixture into tart shell and return to 350 degree F oven and bake for 25 minutes or until center is set. Let cool.
Whip cream, cinnamon, and sugar to desired consistency.