Sift whole wheat flour and cornstarch into a bowl and stir in sugar and salt. Cut in butter until dough resembles a coarse, crumbly texture (this can also be done in a food processor). Mix in cream until dough comes together. Shape dough into a disc, wrap and chill at least 30 minutes.
Preheat oven to 400 degrees F. and line a baking tray with parchment paper.
On a lightly floured surface, roll out dough in a rectangle 12 by 9 inches. Using a pastry wheel, cut dough into 12 rectangles and place on baking tray. Bake for 12 to 15 minutes until lightly browned. Allow to cool.
For cheesecake filling, beat cream cheese until smooth. Gradually add sugar and vanilla and beat until smooth. Pour in whipping cream and whip until filling thickens. Chill until ready to assemble.
For assembly, simmer balsamic vinegar and 2 Tbsp sugar for about 3 minutes, until thickened. Pour over strawberries and toss to coat.
In a large glass dish, arrange 4 graham crackers at bottom of dish and spread with a third of the cream. Top with a third of strawberry mixture and repeat with 2 more layers. Whip cream to soft peaks and stir in remaining 2 Tbsp sugar. Spread over top of the trifle as the final layer. Serves 6 to 8.