• Preheat oven to 325°F. Line a 9×13-inch baking dish with parchment paper, leaving some overhang for easy removal. Set aside.

Blackberry Topping

• In a large saucepan over medium-high heat, add 2 ½ cups of blackberries, granulated sugar, and brown sugar. Stir until the sugar dissolves and the berries begin to release their juices and soften.
• In a small bowl, whisk together the cornstarch and water until smooth. Pour the mixture into the saucepan and continue stirring until thickened to a jam-like consistency that coats the back of a spoon.
• Remove from heat and stir in the lemon zest. Gently fold in the remaining blackberries.
• Transfer the mixture to a bowl and let it cool slightly, then place it in the refrigerator to chill while you prepare the crust and filling.

Crust

• To toast the pecans, add them to a medium skillet over medium heat. Cook, stirring frequently, until fragrant and lightly browned, about 3 to 5 minutes. Remove from heat and let cool.
• When ready, in a medium bowl, combine melted butter, flour, and toasted pecans. Mix until evenly combined.
• Press the mixture firmly into the bottom of the prepared baking dish.
• Bake 15 minutes. Remove from the oven and let cool to room temperature.

Filling

• Add heavy cream to a mixing bowl. Start mixing at the lowest speed, and then gradually increase speed to medium until the cream starts to get thicker. (The gradual progression prevents you from spraying yourself with cream.)
• When the cream starts to thicken, stop the mixer. Slowly add in the confectioners' sugar and then resume mixing again, starting with low speed and increasing to medium speed, and eventually moving to a high speed. The cream will thicken and start to peak.
• In a separate large bowl, add cream cheese and beat until creamy.
• Gently fold the whipped cream mixture into the cream cheese.
• Spread the filling evenly over the cooled crust.
• Spoon the chilled blackberry topping over the filling and gently spread it into an even layer.
• *Top with more blackberries if you would like. (I added some extra in my images.)
• Cover and refrigerate for at least 4 hours, or until fully set. For best results, chill overnight before slicing and serving.