In a medium saucepan, combine fresh blueberries, granulated sugar, brown sugar, and water over medium heat. Gently smash some blueberries with a fork to release juices. Once boiling and sugar dissolves, mix in cornstarch. Stir until thickened, remove from heat, and fold in remaining blueberries, lemon zest, and juice. Cool completely.

Preheat oven to 325°F (165°C). In a mixing bowl, combine melted butter, flour, and chopped pecans until blended. Press evenly into the bottom of a greased 9x13-inch pan. Bake for 15 minutes or until lightly golden. Cool completely.

In a chilled mixing bowl, whip heavy cream until stiff peaks. In a separate bowl, combine cream cheese and powdered sugar until smooth. Gently fold whipped cream into cream cheese mixture. Spread filling over cooled crust, smoothing the top.

Once the topping has cooled, spoon it over the cheesecake filling evenly without disturbing the filling. Cover with plastic wrap and refrigerate for at least 3 hours, preferably overnight.

Slice the dessert into squares with a sharp knife. Wipe the blade between cuts for cleaner edges. Enjoy as a refreshing treat!