01 - Preheat oven to 325°F. Grease a 9-inch springform pan and line the bottom with parchment paper.
02 - In a medium bowl, combine graham cracker crumbs, melted butter, and sugar until evenly moistened. Press the mixture firmly and evenly into the bottom of the prepared pan. Bake for 10 minutes, then set aside to cool slightly.
03 - In a large bowl, beat the cream cheese with an electric mixer until completely smooth. Add sugar and continue beating until light and creamy. Add eggs one at a time, mixing thoroughly after each addition. Blend in vanilla extract, sour cream, flour, and lime zest until just combined — do not overmix.
04 - Pour the filling over the cooled crust and smooth the top with a spatula. Bake for 50 to 60 minutes, until the center is just set with a slight jiggle remaining. Turn off the oven, crack the door open, and let the cheesecake cool inside for 1 hour.
05 - Transfer the cheesecake to the refrigerator and chill for at least 4 hours or overnight for best results.
06 - In a small saucepan over low heat, combine guava paste, water, and fresh lime juice. Stir continuously until the paste melts into a smooth, pourable sauce. Let cool slightly before using.
07 - Pour or spread the guava topping evenly over the chilled cheesecake. Refrigerate for another 30 minutes to allow the topping to set.
08 - Run a thin knife around the edge of the cheesecake before releasing the springform pan sides. Slice into portions and serve chilled.