• Place heavy cream and powdered sugar in the bowl of a stand mixer. Mix with whisk attachment until stiff peaks form.
• Scrape whipped cream into another bowl and place in refrigerator until ready to use.
• Zest and mince lemon peel; then juice half the lemon. (Reserve other half for another use.)
  
• Add cream cheese, zest, and lemon juice to the stand mixer bowl. Beat until smooth with paddle attachment.
• Gently fold half of the whipped cream into cream cheese mixture with a spatula.
• Fold remaining whipped cream into cream cheese. Set aside.

To assemble cake:

• Spread a thin layer of the whipped cream mixture on a platter or in the bottom of a large pan.
• Top with 6 graham crackers (lay 4 next to each other - vertical sides touching - and two along the top; see picture).
• Cover crackers with layer of the whipped cream mixture.
• Top with half of the blueberries.
• Cover blueberries with just need enough of the whipped cream mixture to hold the next row of graham crackers in place, then add another layer of crackers.
• Top crackers with a layer of the whipped cream mixture.
• Cover whipped cream with half of the sliced strawberries.
• Spread strawberries with just enough of the whipped cream mixture to hold the next row of graham crackers in place, then add another layer of crackers.
• Cover top and sides of cake with remaining whipped cream mixture.
  
• Cover cake and refrigerate for at least 4 hours or overnight.
• Before serving, decorate the top of the cake with remaining strawberries and blueberries.
• Slice and serve. Enjoy!