Mix together the white and brown sugars in a small bowl.
Pour half the sugar mixture into a separate mixing bowl and blend with butter, orange zest, and orange juice, and cinnamon. Spread the butter mixture on one side of each slice of bread. Cut each slice of bread in half diagonally. Arrange the bread triangles in an overlapping fashion in an 8x8 inch baking dish with the buttered side down.
Place the remaining sugar, grated chocolate, milk, cream, and eggs into a blender, and blend until thoroughly mixed. Pour the chocolate mixture over the bread, making sure to evenly cover the bread. Cover and refrigerate the prepared dish for 1 hour.
Preheat an oven to 350 degrees F (175 degrees C).
Bake the bread pudding until golden brown and set, 30 to 40 minutes.
