Preheat the oven to 160°C (320°F). Line a small springform pan (6-inch) with parchment paper.

In a bowl, mix graham cracker crumbs, melted butter, and sugar until combined. Press the mixture evenly into the bottom of the prepared pan. Bake for 10 minutes, then let cool.

In a separate bowl, beat the cream cheese and sugar until smooth. Add sour cream and vanilla extract, and mix well.

Beat in the egg until just combined, being careful not to overmix.

Pour the filling over the crust and smooth the top with a spatula.

Bake for 40 minutes, or until the edges are set and the center is slightly jiggly. Turn off the oven and let the cheesecake cool inside with the door slightly open.

Refrigerate for at least 4 hours, or overnight, before serving.