½cup(1 stick) cold unsalted butter, cut into small cubes
Instructions
Preheat the oven to 350°F. Line a 9x9" baking pan with parchment paper or grease with butter or nonstick spray. Set aside.
In a food processor, pulse the cookies together with brown sugar, ground cinnamon, and ground ginger until you get coarse crumbles. Then slowly add the melted butter and pulse until all ingredients are well combined.
Spoon the cookie crust mixture into the bottom of the prepared baking pan. Then use a spatula to help gently press down and even out the crust so that you get an even layer of crust all around and it reaches into the corners and sides. Try to make sure there are no cracks in the crust where batter can seep through.
Bake at 350°F for 6 to 8 minutes. Remove from the oven and allow to cool slightly at room temperature for about 10 minutes.
In a large bowl using a hand mixer (or a stand mixer), beat the softened cream cheese with the granulated butter until smooth. Then add the eggs one at a time. Beat in the pumpkin puree, spices, sour cream, and vanilla, just until all ingredients are well incorporated and the mix is smooth.
Once the crust has cooled to room temperature, pour the filling batter on top. Then make the streusel.
In a separate large bowl, mix together the old fashioned oats, light brown sugar, granulated sugar, ground cinnamon, and flour. Then use your hands to cut in the cold butter cubes, pressing your fingers together to mix in the butter with the other ingredients. It's ok to have some larger pieces of butter here and there, but for the most part, you'll want to press the butter into the other ingredients enough so that they are in smaller crumbly pieces.Sprinkle the streusel topping evenly over the filling. Be sure there is topping all along the corners and the sides.
Cover the pan loosely with aluminum foil. Place the prepared baking pan into the oven and bake at 350°F for 30 minutes. Then at 30 minutes, remove the foil top, and bake for another 15 minutes.
After the bars have baked for 45 minutes total, remove from the oven and allow to cool in the pan on a cooling rack for at least 30 minutes.
Notes
Baking the cheesecake: Be careful not to overbake the cheesecake. Even if the sides are still a little jiggly, if the center is set it's ready to remove from the oven and start to cool. Refrigeration: Once you've cut the cheesecake into bars, refrigerate until you're ready to serve. Do not store them at room temperature.