Bake the cake per the recipe, cool and cut into 1-inch cubes. Vanilla or lemon pound cake may be substituted, if desired.
Separate the raspberries reserving 2/3 cup to garnish the top.
In a medium bowl toss raspberries with 3 Tbsp granulated sugar. Let sit for 5 minutes, then mix with the pie filling until combined.
In a separate medium bowl, whip together both softened cream cheese, lemon juice, 1 1/2 cup heavy cream, 1 1/2 cup powdered sugar. Whip for 2-3 minutes until combined then fold in the lemon zest by hand.
In a separate medium bowl whip the remaining 2 1/2 cup heavy cream with 1/2 cup powdered sugar use more if desired.
Whip until stiff peaks form. Fold 2 cup whipped cream into the cheesecake mousse. Reserve the remaining for the topping.
Assemble: In a large bowl or trifle bowl layer the ingredients beginning with cubed cake, raspberry filling then cheesecake mousse. Repeat layers until all ingredients have been used.
Frost the top with the remaining whipped cream and garnish with reserved 2/3 cup raspberries, lemon zest and grated white chocolate.
Chill for at least 4 hours or overnight before serving.