01 - Preheat oven to 325°F. Line a standard 12-cup muffin tin with paper liners.
02 - In a medium bowl, combine graham cracker crumbs, melted butter, and sugar. Stir until the crumbs are evenly moistened and resemble wet sand.
03 - Divide the crumb mixture evenly among the 12 muffin cups, using roughly 1 tablespoon per cup. Press firmly into the bottoms using the back of a spoon to create a compact, even layer.
04 - In a large bowl, beat the softened cream cheese with an electric mixer until completely smooth and creamy, scraping down the sides as needed.
05 - Add granulated sugar to the cream cheese and beat on medium speed until well incorporated and no lumps remain.
06 - Mix in the egg, vanilla extract, and sour cream. Beat until just blended—avoid overmixing to prevent cracks during baking.
07 - Spoon or pipe the cheesecake batter evenly into the prepared crusts, filling each liner about three-quarters full.
08 - Bake for 18 to 20 minutes, until the centers are almost set but still have a slight jiggle. Do not overbake—the cheesecakes will continue to set as they cool.
09 - Let the cheesecakes cool in the muffin tin for 10 minutes, then transfer to a wire rack to cool completely. Refrigerate for at least 1 hour before serving to allow the filling to firm up properly.
10 - Before serving, top each mini cheesecake with your choice of fresh berries, chocolate ganache, caramel sauce, whipped cream, or crushed toppings.