1.Preheat the oven to 150°C. Grease a 22cm springform pan; line base and side with baking paper, extending the paper 3cm above the edge.
2.Split vanilla bean in half lengthways; scrape seeds into a large bowl of an electric mixer. Add ricotta, honey, sugar and rind to bowl; beat with an electric mixer on medium-high speed for 3 minutes or until smooth.
3.Beat in eggs, one at time, until just combined. Stir in chocolate and half the grapes. Pour mixture into pan; top with remaining grapes.
4.Bake cheesecake for 55 minutes or until the centre is almost firm to touch. Cool in the oven with the door ajar.
5.Refrigerate cheesecake for 4 hours, or until firm.
6.Just before serving, top cheesecake with extra grapes; drizzle with extra honey.
Buy fresh ricotta cut from a wheel from a deli or from the deli counter of a supermarket for the best texture. Pre-packaged ricotta will be too wet for this recipe. Cooling the cheesecake in the oven after it has been turned off, ensures that it will cool slowly and prevent the top from cracking.