Preheat your oven to 350°F (175°C). Line a 9x9-inch baking pan with parchment paper.

In a bowl, mix graham cracker crumbs, sugar, and melted butter until combined. Press this mixture into the bottom of the prepared pan to form an even crust. Bake for 8–10 minutes and let cool.

In a large mixing bowl, beat the cream cheese and sugar until smooth. Add the eggs one at a time, mixing well after each. Stir in the vanilla extract. Pour this cheesecake mixture over the baked crust and spread it evenly.

In a saucepan over medium heat, combine peaches, brown sugar, cinnamon, and nutmeg. Cook until the peaches release their juices, about 5–7 minutes.

Stir in the cornstarch mixture and cook until it thickens. Let this peach mixture cool slightly, then spoon it evenly over the cheesecake layer.

In another bowl, mix the flour, brown sugar, and cinnamon. Cut in the cold butter until the mixture looks crumbly. Sprinkle this streusel over the peach layer.

Bake for 35–40 minutes or until the cheesecake is set and the topping is golden brown. Let the bars cool completely, then refrigerate for at least 2 hours or overnight to firm up.

Cut into squares, drizzle with caramel sauce if you like, and serve chilled.