Preheat the oven to 325°F (165°C).

Crush graham crackers into fine crumbs using a food processor or by placing them in a ziplock bag and crushing with a rolling pin.

In a medium bowl, mix the graham cracker crumbs, melted butter, and granulated sugar until well combined.

Press the mixture evenly into the bottom of a 9 inch springform pan. Bake for 10 minutes, then remove from the oven and let cool.

In a large bowl, beat the Greek yogurt and cream cheese with an electric mixer until smooth.

Add eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

In a microwave-safe bowl, heat the chopped dark chocolate and heavy cream in 30-second intervals, stirring between each interval, until the chocolate is melted and the mixture is smooth.

Fold the melted chocolate mixture into the cheesecake filling until well combined.

Pour the filling into the cooled crust. Bake for 1 hour, 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 ajar for 1 hour.

Remove from the oven and let cool completely on a wire rack. Refrigerate for at least 2 hours before serving.

Remove the cheesecake from the springform pan and slice. Serve each slice chilled.