Preheat the oven to 350°F (177°C). Line a 9×9-inch baking pan with parchment paper, leaving enough overhang on the sides to lift the bars out later.
In a medium bowl, combine the graham cracker crumbs, melted butter, and granulated sugar.
Stir until the mixture resembles damp sand, then press it firmly and evenly into the bottom of the prepared baking pan.
Add the softened cream cheese, eggs, granulated sugar, vanilla extract, and salt to a large mixing bowl.
Beat with a hand mixer until smooth and creamy, scraping down the sides of the bowl as needed.
Spread the cheesecake filling evenly over the graham cracker crust.
Scatter the diced peaches evenly over the cream cheese layer.
In another medium bowl, whisk together the flour, brown sugar, cinnamon, and salt.
Pour in the melted butter and stir until coarse crumbs form.
Sprinkle the crumble topping evenly over the peaches.
Bake the Peach Cobbler Cheesecake Bars for 35–40 minutes, or until the center is mostly set and the crumble topping is lightly golden.
Transfer the pan to a wire rack and allow the bars to cool completely for about 1 hour.
Refrigerate for at least 1 hour, or until fully chilled and firm.
Lift the bars from the pan using the parchment paper overhang, then slice into squares and serve