Step 1

Lightly grease the bottom and sides of a 7-by-3-inch round cake pan with a removable bottom with the softened butter or cooking spray. Cut out a circle of parchment and use it to line the bottom of the pan.

Step 2

Make the crust: In the bowl of a food processor, process the crumbs, sugar and salt until combined, about 30 seconds. Add the melted butter and vanilla and process until the crumbs are uniformly damp, about 30 seconds more. (Alternately, in a large bowl, combine the crumbs, sugar, salt, butter and vanilla and mix with a flexible spatula or with your hands.)

Step 3

Transfer the crumbs to the prepared pan and, using your fingers, press firmly into the bottom of the pan and about 1 inch up the sides. Transfer to the freezer while you prepare the filling.

Step 4

Make the filling: In a small bowl, whisk together the sugar, cornstarch and salt until combined.

Step 5

In the bowl of a stand mixer fitted with the paddle attachment, or using a large mixing bowl and a hand mixer, mix the cream cheese on low speed until smooth, 30 seconds to 1 minute, stopping the mixer and scraping the bowl with a flexible spatula as needed.

Step 6

Slowly, add the sugar mixture until combined, stopping the mixer and scraping the bowl as needed, about 1 minute.

Step 7

Add the heavy cream and vanilla and mix on medium just until combined, about 30 seconds. Add the eggs and yolk, one at a time, and mix only until combined, scraping the bowl as needed.

Step 8

Using a flexible spatula, gently fold the filling one last time and pour it into the prepared pan. The filling will rise above the edge of the crust.

Step 9

Add 1 cup of water to the insert of your Instant Pot or multicooker. Use the trivet’s handles or an aluminum sling (see NOTES), to lower the cake into the pot. Cover, set the steam valve to PRESSURE (or SEALING) and turn to HIGH. After the cooker reaches high pressure, which takes 5 to 10 minutes, cook for 26 to 30 minutes (at 26 minutes, the center will be slightly softer and creamier than the edges and the cake a bit more lush; at 30 the cake is set and dense — in the best cheesecake way possible).

Step 10

Let the pressure release naturally, 20 to 25 minutes, then take the lid off. Water will have accumulated under the lid and, as you remove it, it will drip on the cake. Do not worry — simply blot up the water with a paper towel.

Step 11

Carefully lift the pan from the pot using potholders and the trivet handles or foil sling. Place it on the heatproof surface (the trivet serves as a wire cooling rack) and very gently run a thin knife around the perimeter of the warm cake. Let the cake cool to room temperature, about 1 hour and 30 minutes.

Step 12

Cover with plastic wrap, transfer to the refrigerator and let chill for at least 4 hours and preferably overnight.

Step 13

Remove the sides of the pan from the cake, running a knife around the edge again to dislodge it, if necessary. Remove the pan bottom by sticking a long knife between it and the parchment paper. Peel off the parchment and place the cake on a serving plate.

Step 14

Make the topping: In a medium bowl, whisk together the sour cream, confectioners’ sugar and vanilla extract until combined. Spread over the top of the cake. Chill the cake for another 30 minutes, or until the topping has firmed.

Step 15

For clean slices, use a large knife dipped in hot water and dried between each cut. Add berries to the plate or top of the cake, if using.

Step 16

NOTES: To crush the graham crackers: It is best to use a food processor to turn the crackers into fine crumbs. If using a rolling pin and a zip-top bag to crush the crackers, you may need to use your hands to break up larger chunks.

Step 17

To make a tinfoil sling: Fold a 20-inch rectangular piece of heavy-duty aluminum foil into a strip about 4 inches wide. Place the strip into the Instant Pot to test its size and bend it up to create handles. Place the foil strip under your pan and lower it into the pressure cooker using the foil “handles.” To remove, use a kitchen towel or mitts to grab the foil handles to lift out the pan.