Grease a 7-inch springform pan. In a bowl, mix graham cracker crumbs with melted butter, then press into the bottom of the pan. Chill for 10 minutes.
In a large bowl, beat cream cheese and sugar until smooth. Add eggs one at a time, mixing after each addition.
Stir in sour cream, heavy cream, RumChata, lemon zest, vanilla, and flour until well combined.
Gently fold in chopped strawberries.
Pour the batter over the crust in the prepared pan.
Cover tightly with aluminum foil.
Pour 1 cup of water into the Instant Pot. Place a trivet inside and set the cheesecake pan on top.
Seal the Instant Pot lid and cook on high pressure for 35 minutes. Let the pressure release naturally for 10 minutes, then quick-release the remaining pressure.
Remove cheesecake from the Instant Pot and let cool completely before refrigerating for at least 4 hours or overnight.
Top with whipped cream, fresh strawberries, and lemon slices before serving.