In a large pan combine 1 1/2 cups blueberries, sugar, and brown sugar. Cook over medium high heat and stir constantly. Stir until sugar is combined and blueberries start to pop and come to a boil.
Dissolve cornstarch in water. Add the cornstarch/water mixture in the pan with the blueberries and stir until the mixture becomes thick.
After it has thickened, remove from heat and add the remaining 2 cups of blueberries, then add in the lemon zest and stir in gently.
Cool to room temp or refrigerate until ready to use.
Grease a 9x13 inch glass pan. For the crust, melt the butter and stir in the flour and pecans.
Press crust evenly into the bottom of the prepared pan. Cook at 325 for about 15 minutes or until lightly browned. Then let crust cool to room temperature.
For the filling, whip the heavy cream and set aside.
In another mixing bowl beat the cream cheese and powdered sugar together until smooth. Then add the whipped cream in with the cream cheese mixture and combine. Then spread over the cooled crust.
Spread the blueberry topping over all. Let set in the fridge for about an hour.
Notes
If you do not have the simple ingredients to make the pecan crust, then you can always substitute it for a graham cracker crust.