Prepare a 7-inch springform pan by lining the bottom with parchment paper and greasing the sides.

In a medium bowl, mix graham cracker crumbs, sugar, melted butter, and salt. Press this mixture into the bottom and about 1 inch up the sides of the pan. Freeze while you prepare the other parts.

In a medium saucepan, heat sugar over medium heat, stirring constantly. The sugar will clump and then melt into a deep amber liquid in about 8-10 minutes.

Once melted, add the butter carefully, stirring until melted, about 2 minutes.

Slowly drizzle in the heavy cream while stirring. The mixture will bubble. Let it boil for 1 minute.

Remove from heat and stir in sea salt. Let it cool slightly. Reserve 1/4 cup for topping.

Beat cream cheese and sugar in a large bowl until smooth and creamy.

Add eggs one at a time, beating well after each addition. Stir in sour cream, vanilla, and flour until combined.

Remove the crust from the freezer. Pour half of the cheesecake batter over it.

Drizzle half of the remaining caramel sauce (not the reserved 1/4 cup) over the batter. Use a knife to swirl gently.

Pour the remaining cheesecake batter on top. Drizzle with the rest of the caramel sauce and swirl gently again.

Pour 1 cup of water into the inner pot of your pressure cooker.

Create a foil sling with a 20-inch piece of foil and place it in the pot.

Cover the top of the pan with aluminum foil. Put the pan on the sling in the cooker.

Secure the lid and set the valve to sealing. Cook on High pressure for 35 minutes.

After cooking, let the pressure release naturally for 10 minutes, then quick-release any remaining pressure.

Use the sling to remove the cheesecake from the cooker. Remove the foil cover and let it cool on a wire rack for 1 hour.

Refrigerate for at least 6 hours or overnight.

Before serving, run a knife around the edge and release the springform ring. Drizzle with the reserved caramel sauce and sprinkle with flaky sea salt. Add whipped cream and toffee bits if desired.