Preheat the Oven: Preheat the oven to 325°F (163°C) and grease a 9-inch springform pan.
Prepare the Crust: Mix graham cracker crumbs, sugar, and melted butter until combined. Press into the bottom of the pan and bake for 10 minutes. Let cool.
Make the Cinnamon Roll Layer: In a bowl, mix butter, brown sugar, and cinnamon. Spread over the crust.
Prepare the Cheesecake Filling: Beat cream cheese and sugar until smooth. Add eggs one at a time, then mix in vanilla and sour cream. Pour half over the cinnamon layer.
Add the Cinnamon Swirl: Mix brown sugar and cinnamon. Sprinkle half over the batter, pour in the remaining cheesecake filling, then sprinkle the rest. Use a knife to swirl.
Bake the Cheesecake: Place the pan in a water bath and bake for 55-65 minutes, until set but slightly jiggly. Let cool in the oven for 1 hour, then refrigerate for at least 4 hours.
Make the Frosting: Beat cream cheese and butter until smooth. Add powdered sugar and vanilla, mixing until creamy. Add milk if needed.
Serve: Spread frosting over the chilled cheesecake, slice, and enjoy!