1. Prepare the pan. Lightly grease a 9 x 13-inch metal or glass dish. Line it with parchment paper if you want to lift out the entire dessert before slicing. Leave enough paper hanging over two sides to form handles.

2. Make the cookie crumbs. Process the vanilla wafers until they become fine, even crumbs. Large pieces can make the crust break apart when the dessert is sliced.

3. Form the crust. Stir the cookie crumbs, melted butter, granulated sugar, and salt together until every crumb looks evenly moistened. The mixture should hold together when squeezed between two fingers.

4. Press and chill. Transfer the mixture to the prepared dish. Press it into a compact, level layer with the flat bottom of a measuring cup. Pay close attention to the corners. Refrigerate for 30 minutes.

5. Prepare the strawberries. Rinse the strawberries before removing their tops. Dry them thoroughly. Dice them into small pieces, then place them between clean paper towels for several minutes to remove surface moisture.

6. Make the strawberry filling. Beat the 16 ounces of softened cream cheese on medium speed for 60 to 90 seconds, or until completely smooth. Add the sifted powdered sugar, vanilla, and lemon juice. Beat on low speed until combined, then briefly mix on medium speed.

7. Fold in the first whipped topping. Use a rubber spatula to fold 1 cup of thawed whipped topping into the cream cheese mixture. Fold only until no white streaks remain.

8. Add the strawberries. Gently fold the dried strawberry pieces into the filling. Do not beat them with the mixer, since this can release too much juice.

9. Add the strawberry layer. Spoon the filling over the cold crust. Spread it into an even layer with an offset spatula. Refrigerate for 20 minutes.

10. Prepare the blueberries. Set aside 1/2 cup of whole blueberries. Place the remaining 1 cup in a wide bowl and mash them thoroughly with a fork or potato masher. Drain off any large pool of thin juice. The thick mashed fruit will add natural purple color without making the filling too loose.

11. Make the blueberry filling. Beat the remaining 8 ounces of softened cream cheese until smooth. Add the powdered sugar, vanilla, and lemon juice. Mix until creamy.

12. Finish the blueberry layer. Fold the mashed blueberries into the cream cheese mixture. Fold in 1 cup of thawed whipped topping, followed by the reserved whole blueberries.

13. Add the blueberry layer. Spoon small portions of the blueberry filling across the chilled strawberry layer. Gently connect them with an offset spatula. This method prevents the lower layer from being pulled upward. Chill for another 20 minutes.

14. Whip the cream. Place the cold heavy cream, powdered sugar, and vanilla in a chilled mixing bowl. Beat on medium speed until the cream thickens. Continue just until stiff peaks stand upright when the beaters are lifted.

15. Add the topping. Spoon the whipped cream across the blueberry layer. Spread it gently without pressing into the filling.

16. Chill the dessert. Cover the dish without allowing the covering to touch the cream. Refrigerate for at least 6 hours. Overnight chilling gives the cleanest slices.

17. Decorate and slice. Add strawberries, blueberries, and white chocolate curls shortly before serving. Dip a sharp knife in hot water, dry it, and cut the dessert into 12 squares. Clean and warm the knife between cuts.

18. Serve. Keep the dessert cold until serving. Return leftovers to the refrigerator promptly.