Preheat your oven to 400°F (200°C). Slice 4 fresh peaches, tossing them in a bowl with granulated sugar, cinnamon, and a pinch of nutmeg. Spread the peach slices evenly on a baking sheet and roast for 7-15 minutes, until they become tender and fragrant.

Reduce the oven temperature to 350°F (175°C). In a medium bowl, combine graham cracker crumbs, melted salted butter, and a touch of brown sugar. Press this mixture firmly into the bottom of a greased 9-inch springform pan to form a solid crust. Bake for about 10 minutes.

Prepare the cinnamon streusel topping by mixing melted salted butter with brown sugar, all-purpose flour, cinnamon, and a pinch of salt until crumbly. Bake at 350°F (175°C) for about 8 minutes.

In a large mixing bowl, beat the cream cheese until creamy. Gradually add granulated sugar, followed by eggs, one at a time. Blend in sour cream and vanilla extract to create a rich filling.

Pour half of the cheesecake batter into the pre-baked crust, layer the roasted peaches, sprinkle with streusel, then pour the remaining batter on top.

Create a water bath by placing the springform pan in a larger baking dish filled with boiling water. Bake at 350°F (175°C) for 88-91 minutes.

Turn off the oven and crack the door open. Allow the cheesecake to cool in the oven for 1 hour, then refrigerate for at least 6 hours before serving.

To serve, top with reserved roasted peaches and remaining streusel. Drizzle any peach juices over the top.