Preheat your oven to 325°F (163°C).
Combine graham cracker crumbs and melted butter in a bowl. Mix until evenly coated.
Press the mixture firmly into the bottom of a springform pan and slightly up the sides.
In a large mixing bowl, beat the softened cream cheese until smooth.
Add granulated sugar, vanilla extract, and mix until fully combined.
Add eggs one at a time, blending well after each addition.
Fold in sour cream and mix until smooth.
In a separate bowl, mix brown sugar, cinnamon, and 2 tbsp of the cheesecake batter to form the swirl.
Pour half of the cheesecake batter into the crust, then dollop with the cinnamon mixture, and layer the remaining batter on top.
Use a knife to swirl the cinnamon layer through the batter gently.
Bake for 50-60 minutes or until the center is set but jiggles slightly when shaken.
Turn off the oven, crack the door open, and let the cheesecake cool inside for 1 hour.
Refrigerate for at least 4 hours, preferably overnight.
For the frosting, beat cream cheese with powdered sugar and milk until smooth.
Spread the cream cheese frosting over the chilled cheesecake before serving.