Instant Pot Blueberry Swirl Cheesecake

Fold a 24-inch-long (60-cm) piece of foil in half lengthwise and in half again lengthwise, to form a foil sling 3 inches (8 cm) wide and about 24 inches (60 cm) long. Place a wire rack or metal trivet* on the bottom of the Instant Pot insert.

In a small saucepan over medium heat, combine the blueberries, sugar, lemon juice, and cornstarch. Bring to a boil, reduce the heat to low, and simmer until the mixture begins to thicken but is still syrupy, 5 to 10 minutes. Let cool to room temperature, then refrigerate. The compote will thicken more as it cools.

Place the graham crackers in a resealable plastic bag. Use a rolling pin or your hands to crush until fine crumbs form. Alternatively, you can blitz the crackers in your food processor.
Dump the crumbs into a small bowl and stir in the sugar. Pour the melted butter over the crumb mixture and use a fork to combine thoroughly.
Press the crumbs into the bottom of a 7-inch (18-cm) springform pan, covering the bottom and at least 1 inch (25 mm) up the sides. Use the bottom of a glass to smooth the surface. Stash the pan in the freezer until needed.

In the bowl of a stand mixer on medium speed, or in a large bowl using an electric hand mixer, beat the cream cheese, ricotta, and sour cream together until just combined. Add the eggs one at a time, beating well and scraping the bowl after each addition. Stir in the cornstarch, lemon juice, and vanilla.

Remove the crust from the freezer and pour the cheesecake filling into the crust. Top with 1/2 cup of the blueberry compote and use a knife to swirl the compote into the filling. Smooth the top with an offset spatula, if needed.
Pour 1 cup of water into the Instant Pot insert. Place the springform pan in the center of the foil sling and move the sling and pan into an 8-inch cake pan. (If your Instant Pot is smaller than 8 quarts, wrap the bottom of the springform pan with aluminum foil instead.) Place the cake pan onto the rack inside the insert. Tuck the sling into the sides.
Seal the top of the Instant Pot and cook on high pressure for 25 minutes. Allow for a natural release for 15 minutes, then switch to manual release. Remove the lid carefully to avoid dripping moisture onto the cheesecake.
Use the sling to remove the springform pan. Dab the top of the cheesecake with paper towels if necessary, to remove any collected moisture.
Refrigerate the cheesecake for at least 6 hours, but preferably overnight.
When ready to serve, remove the cheesecake from the refrigerator. Run an offset spatula around the inside edge of the pan. Open the springform pan and place the cheesecake on a serving platter. Top the cheesecake with the remaining blueberry compote. Cut and serve.