Preheat oven to 350 degrees. Line a 9x13 baking dish with foil and spray with non-stick spray.
In a large mixing bowl, add the cake mix, egg, and butter. Beat with a hand mixer until a firm dough is formed.
Press the cake crust into the bottom of the prepared baking dish and set aside.
Add the sweet potatoes, cream cheese, sugar, egg, and spices in a food processor. Pulse the mixture until it’s creamy. Pour the cheesecake batter over the crust. Spread the cheesecake out evenly and to the edges of the pan.
Bake this for 23-25 minutes until the cheesecake is set. Once the cheesecake is done baking, prepare the topping.
In a small bowl, whisk the Greek yogurt, vanilla, and sugar together.
Spread the yogurt mixture on top of the baked cheesecake evenly.
In a small bowl, add the honey and oats granola, white chocolate chips, and pumpkin pie spice. Stir together and sprinkle all over the top of the yogurt topping.
Bake for another 5 minutes. Allow the cheesecake bars to cool completely before refrigerating for several hours, preferably overnight.