Step 1: Prepare the Blueberry Layer

1. Cook Blueberries: In a medium saucepan, combine the fresh blueberries, granulated sugar, lemon juice, cornstarch, and water. Cook over medium heat, stirring gently until the mixture comes to a boil and thickens, about 5-7 minutes. Remove from heat and let cool.

Step 2: Make the Cheesecake Layer

1. Beat Cream Cheese: In a large mixing bowl, beat the softened cream cheese with an electric mixer until smooth.
2. Add Sugar and Vanilla: Gradually add the powdered sugar and vanilla extract, mixing until well combined.
3. Whip Cream: In another bowl, whip the heavy cream until stiff peaks form.
4. Combine: Gently fold the whipped cream into the cream cheese mixture until fully incorporated.

Step 3: Assemble the Lasagna

1. Layer Graham Crackers: In a 9×13 inch baking dish, place a layer of graham crackers at the bottom.
2. Add Cheesecake Layer: Spread half of the cheesecake mixture over the graham crackers.
3. Add Blueberry Layer: Spoon half of the blueberry mixture over the cheesecake layer.
4. Repeat Layers: Add another layer of graham crackers, followed by the remaining cheesecake mixture and then the remaining blueberry mixture.
5. Top with Whipped Topping: Finish with a layer of whipped topping spread evenly over the top.

Step 4: Chill

1. Refrigerate: Cover the dish with plastic wrap and refrigerate for at least 4-6 hours, or overnight, to allow the layers to set.

Step 5: Serve

1. Garnish: Before serving, garnish with extra blueberries if desired.
2. Slice and Enjoy: Cut into squares and serve chilled.