Using a medium-size sauce pan over medium-high heat, bring the fresh blueberries, cornstarch, lemon juice, vanilla extract, and granulated sugar to a boil, stirring constantly.

As you continue to stir, reduce the heat and simmer for 10-15 minutes. The blueberries will break down into juices as the rest of the mixture thickens.

Remove from heat and pour into a glass bowl to cool completely.

Spray the bottom and sides of an 8-inch square baking pan with a flour-based baking spray, then (optional) place a parchment paper sleeve into the pan, creasing the 2 sides at the edge so the paper doesn’t fall into the batter as it bakes. Lightly spray the parchment paper with the baking spray. Set aside.

Adjust the oven rack to the 2nd level mark (just above center) and preheat the oven to 325ºF.

Using a food processor, pulse the graham crackers into fine crumbs. Add in the melted butter and pulse until the mixture is combined. The texture of the graham cracker crust will be like a wet sand. You can also combine the two ingredients in a mixing bowl.

Spoon the graham cracker crust mixture into the prepared baking pan, pressing down to level the crust using the bottom of a drinking glass or measuring cup.

Bake for 8-10 minutes at 325ºF. Remove from the oven and allow to cool slightly while you make the cheesecake filling.

Using a hand mixer or stand mixer fitted with a paddle attachment, beat the cream cheese on medium-high speed until it’s smooth, creamy, and light in texture (4-5 minutes). Scrape down the sides of the bowl with a spatula as needed.

Add in the eggs, egg white, vanilla extract, granulated sugar, and sifted all-purpose flour, and beat together until just combined. Be careful not to over mix.

Pour the cream cheese filling over top of the slightly cooled graham cracker crust. If needed, level and smooth with a spatula.

Spoon the cooled, thickened blueberry sauce over top of different areas of the cheesecake filling. Then, with a knife or toothpick, swirl the sauce around to create a marbled effect.

Place in the oven and bake for 45-50 minutes at 325ºF. It’s okay to remove the cheesecake bars from the oven if they still have a little jiggle to the center.

Remove from the oven and allow the cheesecake bars to cool completely before moving them to the refrigerator to chill and set for a minimum of 2 hours or—the best option—overnight.

Keep the blueberry swirl cheesecake bars in an airtight container in the refrigerator for up to a week. You can also freeze the bars individually.