Preheat oven to 350 degrees.

Press an unbaked pie crust into a 9" deep dish pie plate. Crimp edges if desired.

In a mixing bowl, beat cream cheese until softened.

Add sweetened condensed milk and beat on high for 2 minutes until lumps are gone. Scrape the sides of the bowl and mix again.

Add pumpkin, eggs, pumpkin pie spice, cinnamon and ginger. Mix on medium low speed until blended. Pour filling into pie crust. 

Bake pie at 350 degrees for 50 minutes, or until sides are set and middle is slightly jiggly. 

Cool pie for at least one hour on rack, then transfer to the refrigerator and cool one hour more.

Preheat oven to 375 degrees.

In a large bowl, mix Snickerdoodle cookie mix and cinnamon packet together. (follow these instructions rather than the ones on the package)

Add melted butter and beaten egg. Stir until moistened.

Spread cookie mix onto a half sheet pan. Bake at 375 degrees for 10 minutes until cookie dough is  crispy, but not cooked all the way through.

With a large spoon, break up the cookie dough into crumbles. If it doesn't crumble, cook a little longer, but don't let it burn.

Cool crumbles while pie is cooling in fridge. Use hands after it has cooled to break into smaller crumbles.

After pie has cooled, sprinkle crumbles on top. Serve with whipped cream if desired.