Preheat the oven to 350°F (175°C).

Prepare the crust by mixing graham cracker crumbs and melted butter.

Bake the crust for 8-10 minutes until lightly golden.

While the crust cools, make the berry swirl by combining mixed berries, lemon juice, and cornstarch in a small saucepan.

Bring the berry mixture to a simmer over medium heat, stirring gently.

Remove the berry mixture from heat and let it cool.

In a mixing bowl, beat the softened cream cheese, sugar, and vanilla until smooth.

Add the egg to the cream cheese mixture and mix until fully incorporated.

Pour the cheesecake mixture over the cooled crust.

Drop spoonfuls of the berry mixture onto the cheesecake filling, then use a knife to swirl them together.

Bake in the preheated oven for about 20-25 minutes or until the edges are set.

Remove from the oven and let them cool in the pan.

Once cooled, refrigerate for at least 2 hours before serving.