Spray a 7" springform pan with nonstick spray ground the crackers in the food processor
In a bowl, mix the graham cracker crumbs with the melted butter
Press this mixture into the bottom and sides of the springform pan. Freeze while making the filling
Place the egg yolks and sugar in a bowl. Using a mixer on medium-high speed, mix until the yolks turn pale yellow and thicken (about 2-3 minutes)
Add the condensed milk and keep mixing. Add the key lime juice and zest. Mix until combined
Pour this mixture on top of the prepared crust
Cover the springform pan with aluminum foil
Make a sling with aluminum foil: Break a long piece of foil and fold into 3. The idea is to get a long thin rectangle (helps remove the pie from the instant pot quicker)
Pour 1 cup of water in the instant pot. Place trivet on top
Put the sling in and place the pie on top. Cover with lid and lock in place
Cook on manual high pressure for 15 minutes (15 MHP)
Let the pie cool for 10 minutes before releasing the pressure (10 NPR)
Remove the pie from the instant pot using the sling and cool and remove the aluminum foil cover. Center should be a bit jiggly
Refrigerate for 3-4 hours or until set
For Topping: Whip cream and slowly add the sugar until the cream becomes stiff. Pipe on top of pie and decorate with zest
Enjoy!