Mix together the crust ingredients and press mixture into the bottom of a 9 1/2-inch springform pan. Bake 10 minutes; remove from oven and set aside. Keep the oven on.
Beat the cream cheese, white sugar, brown sugar and pumpkin pie spice until smooth.
Mix in the sour cream, vanilla extract, whipping cream and sweet potatoes until fully combined. Beat in the eggs one at a time, mixing well after each. Gently pour the filling into the crust.
Bake in the oven for 50-60 minutes, until a tester inserted near the center comes out clean.
Turn off the oven and open the oven door a crack. Let the cheesecake stand in the oven cooling for one hour.
To make the topping, add the brown sugar and salted butter to a small saucepan. Over medium heat, heat and melt the butter and sugar together until smooth. Bring to a low boil then stir in the whipping cream and pecans.
Remove from the heat and pour over the cheesecake top. Store the cheesecake in a closed container in the refrigerator.
Notes
You can skip the topping and use whipped cream if you like!