1. **Prepare the Strawberry Cake Layers:**

– Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

– In a large bowl, combine the strawberry cake mix, egg whites, vegetable oil, milk, and strawberry gelatin mix. Mix until well combined.

– Gently fold in the mashed fresh strawberries if using.

– Divide the batter evenly between the prepared cake pans and bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean.

– Allow the cakes to cool in the pans for 10 minutes, then transfer to wire racks to cool completely.

2. **Prepare the Cheesecake Filling:**

– In a large mixing bowl, beat the softened cream cheese until smooth.

– Add the granulated sugar and vanilla extract, and mix until well combined.

– Add the cornstarch and mix until incorporated.

– Add the eggs one at a time, mixing well after each addition.

– Stir in the heavy whipping cream until the mixture is smooth.

– Pour the cheesecake filling over the cooled strawberry cake layers in the cake pans.

– Bake at 325°F (165°C) for 45-50 minutes, or until the cheesecake is set and the edges are lightly golden.

– Allow the cakes to cool completely, then refrigerate for at least 4 hours or overnight to set.

3. **Assemble the Cake:**

– Once chilled, remove the cakes from the refrigerator. If the cakes have domed on top, level them with a serrated knife to create flat surfaces.

– Place one cake layer on a serving platter. Spread a layer of whipped topping over the cheesecake layer.

– Place the second cake layer on top, aligning it carefully.

– Frost the top and sides of the entire cake with the remaining whipped topping.

– Arrange the sliced fresh strawberries on top of the cake, either in a decorative pattern or scattered evenly.

4. **Optional Glaze:**

– Warm the strawberry jam or preserves in a small saucepan over low heat until it becomes liquid.

– Brush a thin layer of the warm jam over the fresh strawberries to give them a glossy finish.

5. **Serve:**

– Slice the cake and serve chilled. Enjoy!