In a large mixing bowl, combine the softened cream cheese, pumpkin puree, sour cream, sugar, pumpkin pie spice, and vanilla. Mix well using a hand mixer on medium speed, scraping the sides of the bowl as you go.
In a separate bowl, combine the flour, brown sugar, melted butter, and pumpkin pie spice. Mix with a fork until large crumbs form.
Transfer the cheesecake base to a pie plate and spread evenly. Top with the streusel topping and bake at 350 degrees for 25 minutes or until the topping is golden brown and crispy.
Let cool for 10-15 minutes, then whip up the powdered sugar icing and drizzle as desired. Serve with graham crackers, gingersnaps, vanilla wafers, or any of your favorite dippers.