Preheat oven to 350 degrees F (if using a silver springform pan, or 325 degrees F if using a dark nonstick springform pan).
Lightly grease the bottom and sides of a 9-inch spring-form pan. In a mixing bowl, combine the chocolate wafer crumbs, 3 tablespoons of the sugar, and the butter and mix well. Press onto the bottom of springform pan and set aside.
In a large mixing bowl with an electric mixer, combine cream cheese, remaining cup of sugar, vanilla extract and vanilla bean seeds and beat until light and creamy. Add the flour to the cream cheese mixture and beat until smooth. Add the melted chocolate and sour cream and mix well. Add the eggs, 1 at a time, mixing on low speed after each addition until just blended. Pour the batter into prepared pan and bake for 1 hour to 1 hour and 10 minutes, until the center is almost set. Run a sharp knife around the rim of the pan and allow cake to cool on a wire rack before removing rim of pan. Refrigerate at least 4 hours or overnight before serving. Cheesecake may be made up to 2 days in advance before serving and will keep for up to 1 week in the refrigerator.
Serve the cheesecake garnished with fresh strawberries, whipped cream and mint sprigs.