Preheat your oven to 350°F (175°C). In a food processor or a mixing bowl, combine graham cracker crumbs and sugar, then stir in the melted butter until the mixture resembles wet sand. Press this mixture evenly into the bottom of your baking pan to form the crust. Bake for 10 minutes until lightly golden, then set aside to cool slightly.
While the crust cools, beat the softened cream cheese with sugar until smooth and creamy, about 2-3 minutes. Mix in the eggs one at a time, then add vanilla extract and beat until combined. The batter should be glossy and smooth.
Gently fold in the blackberries into the cheesecake batter, saving a few for garnishing if desired. Carefully pour the mixture over the pre-baked crust, spreading it evenly with a spatula. Dot the top with remaining blackberries for a vibrant look.
Bake the bars at 350°F (175°C) for 35-40 minutes, or until the edges are set and the center slightly jiggles when shaken. The top should be lightly golden and the filling creamy and firm.
Remove from the oven and let cool in the pan for about 30 minutes, then transfer to a wire rack to cool completely. Chill in the refrigerator for at least 2 hours to allow the flavors to meld and the bars to set fully.
Once cooled and set, cut into square bars and serve. The bars should be rich, creamy, with a tart burst from the blackberries, and a crisp crust underneath. Enjoy these as a cool, decadent treat when you're craving summer flavors.
