01 - Preheat oven to 350°F. Grease a 9x9-inch baking dish with butter or cooking spray.
02 - Combine flour, melted butter, pecans, sugar, and salt in a bowl. Mix until crumbly and press mixture firmly into the bottom of the prepared dish.
03 - Bake for 18–20 minutes until lightly golden. Remove from oven and let cool completely before adding filling.
04 - Beat cream cheese and powdered sugar in a large bowl until smooth and creamy. Stir in vanilla extract.
05 - In a separate chilled bowl, whip heavy cream with electric mixer until stiff peaks form.
06 - Gently fold whipped cream into cream cheese mixture until fully incorporated and smooth.
07 - Spread cream cheese filling evenly over cooled crust using an offset spatula.
08 - Combine blueberries, sugar, cornstarch, lemon juice, water, and lemon zest in saucepan. Cook over medium heat, stirring constantly, until mixture thickens and becomes glossy, about 6–8 minutes. Remove from heat and cool to room temperature.
09 - Spread cooled blueberry topping carefully over cream cheese layer.
10 - Cover and refrigerate for at least 1 hour to set. Cut into squares and serve chilled.