Step 1

GRAHAM CRACKER CRUSTPrepare a 7 inch springform pan by coating it with a non-stick spray.

Step 3

In a small bowl, combine the graham cracker crumbs, butter, and sugar. Press evenly in the bottom and up the side of the pan. Place in the freezer for 10 minutes.

Step 5

FILLINGIn a large mixing bowl, beat the egg yolks until they are light yellow. Gradually beat in sweetened condensed milk until thickened. Gradually add lime juice and beat until smooth. Stir in sour cream and zest. Pour batter into the springform pan on top of the crust. Cover top of springform pan with aluminum foil.

Step 7

Pour 1 cup of water into the pressure cooking pot, and place the trivet in the bottom. Carefully center the filled pan on a foil sling** and lower it into the pressure cooking pot. Fold the foil sling down so that it doesn't interfere with closing the lid.

Step 9

Lock the lid in place. Select High Pressure and set the timer for 15 minutes. When the cook time ends, turn off the pressure cooker. Let the pressure release naturally for 10 minutes, then finish with a quick pressure release. When the valve drops, carefully remove lid. Remove the pie and check to see if the middle is set. If not, cook for an additional 5 minutes.

Step 11

Remove the springform pan to a wire rack to cool. Remove aluminum foil. When pie is cooled, refrigerate covered with plastic wrap for at least 4 hours. Serve with whipped cream, optional.