Preheat oven to 170 degrees C. Melt chocolate chips in a double boiler or in the microwave, stirring occasionally until smooth. Set aside.
In a medium bowl, beat the cream cheese until smooth and creamy. Gradually add the sweetened condensed milk then beat in the eggs and vanilla. Finally, stir in the melted chocolate. Pour into the prepared crust.
Bake for 1 hour in the preheated oven until the centre is set. Allow cheesecake to cool to room temperature then refrigerate at least 4 hours before serving.