Preheat your oven to 325°F (163°C).
To make the crust, combine graham cracker crumbs, granulated sugar, and melted butter in a bowl. Press the mixture into the bottom of a 9-inch springform pan.
In a large mixing bowl, beat together cream cheese and sugar until smooth. Add vanilla extract and flour, mixing until just combined.
Add eggs one at a time, beating on low speed after each addition just until combined. Do not overmix.
Mix in sour cream and heavy cream until smooth. Stir in key lime juice and mango puree until everything is well combined.
Pour the cheesecake filling over the prepared crust in the springform pan.
Bake the cheesecake in the preheated oven for about 1 hour and 5 minutes or until the edges are set and the center is slightly jiggly.
Turn off the oven, and let the cheesecake cool in the oven with the door ajar for 1 hour.
Chill the cheesecake in the refrigerator for at least 4 hours before serving.