Preheat your oven to 350°F (180°C). Line a 10-inch (25-cm) springform pan with two layers of plastic wrap, long enough to hang over the sides.
Press the cookie dough evenly into a circle along the bottom of the pan, then fold the plastic wrap over the top to cover. Unclasp the pan and freeze the cookie dough disk for at least 30 minutes.
Re-clasp the pan and spray the bottom with cooking spray. Pour the prepared brownie batter into the pan.
Spray the bottom and sides of a 5-inch (12-cm) deep, 8-inch (20-cm) wide cake pan. Press the greased cake pan into the brownie mix until the batter reaches halfway up the sides of the springform pan, creating a well for the other layers.
Bake the brownie for 35 minutes, then remove and cool for 5 minutes. While cooling, reduce oven temperature to 300°F (150°C).
In a large bowl, mix together the cream cheese, sugar, vanilla, and egg until completely smooth and lump-free.
With oven mitts, carefully rotate and press down on the inner cake pan (which is still inside the brownie) to push the baked brownie up the sides of the springform pan, forming a brownie “shell.” Chill the pan in the refrigerator for 30 minutes.
Place a single layer of sandwich cookies (about 14-15) in the bottom of the brownie shell, covering as much surface as possible.
Pour the cheesecake filling over the cookies, spreading it into an even layer. Tap the pan gently to release any big air bubbles.
Bake for 40 minutes at 300°F (150°C), until the cheesecake just jiggles in the center.
Freeze until the cheesecake layer is barely firm to the touch—about 30 minutes.
Arrange another layer of sandwich cookies over the firm cheesecake layer. Carefully place the frozen cookie dough disk on top, pressing it to cover the surface and tucking in any edges.
Bake for another 20 minutes at 350°F (180°C), then chill completely in the springform pan.
When ready to serve, unclasp the pan and carefully remove the cake. Slice and serve each piece with a dollop of whipped cream and, for extra flair, top with another cookie. Enjoy!
Notes
Store leftovers tightly covered in the refrigerator for up to 5 days. For freezing, wrap slices individually and freeze for up to 2 months.