Spray your springform cake pan with cooking spray and set aside.
In a medium bowl, mix together the flour, salt and baking powder.
In a separate bowl, combine the eggs and sugar until well blended, and then stir in the vanilla extract and melted butter.
Gradually add the dry flour mixture into the wet egg mixture until well mixed.
Stir the milk into the batter, followed by the lemon zest and lemon juice until just combined. Be careful not to overmix.
Pour the batter into the greased springform pan. Drop dollops of lemon curd across the top of the cake batter, and use a knife or toothpick to swirl the curd.
Lower the pan into the bottom of the Instant Pot with the trivet and close the lid. Turn the steam valve to the sealing position and select manual high pressure for 30 minutes. Allow the steam to naturally release once finished cooking.
After the steam has released and the pin indicator has dropped, remove the lid. Carefully pull the trivet out of the pot and allow the cake to fully cool before removing from the springform pan. Slice and serve with a dollop of lemon curd or whipped cream, enjoy!
Springform pans are recommended for easy release of the cake. Use a butter knife run under warm water to pull around the edges of the cake if you’re having trouble releasing from the pan.
A 7 inch springform pan will fit inside a 6 qt and above instant pot.
As all lemons vary in size, it's best to grab an extra lemon or two when you're looking to extract the juices. 1 lemon should produce around 2-3 Tbsp of juice, so I would recommend grabbing 2-3 lemons to be safe.