Prepare the crust: Preheat your oven to 325°F (163°C). In a mixing bowl, combine graham cracker crumbs, sugar, and cinnamon. Add melted butter and mix until the crumbs resemble wet sand. Press the mixture firmly into the bottom of a 9-inch springform pan. Bake for 8 minutes, then set aside to cool.

Make the filling: In a large mixing bowl, beat the softened cream cheese with an electric mixer until smooth and creamy. Gradually add sugar and vanilla extract, mixing until fully incorporated. Beat in the eggs one at a time, ensuring each egg is fully mixed before adding the next. Blend in sour cream, heavy cream, and cinnamon until the mixture is silky and free of lumps.

Assemble and bake: Pour the cheesecake filling over the cooled crust. Smooth the top with a spatula. Place the springform pan on a baking sheet and bake for 55-65 minutes, or until the edges are set but the center still has a slight jiggle. Turn off the oven, crack the door open slightly, and let the cheesecake cool inside for 1 hour.

Add the topping: Once the cheesecake has cooled completely, prepare the topping. Brush the melted butter evenly over the surface of the cheesecake. In a small bowl, mix sugar and cinnamon, then sprinkle the mixture generously over the buttered surface to create a crunchy, sweet layer.

Chill and serve: Refrigerate the cheesecake for at least 4 hours or overnight to allow it to set fully. Carefully remove the springform pan before slicing and serving.