Assign XML snippet to serializable object's property

If I have a class like this:

 [Serializable]
 public class Test
 {
    public int Foo {get; set;}
    public object Bar {get; set;}
 }

Then what is the cleanest way to do this:

 Test example = new Test();
 example.Foo = 123;
 example.Bar = SomehowMakeThisInToAnObject("<this><is>Xml</is></this>");
 var xs = new XmlSerializer(typeof(Test));
 string xmlText = xs.Serialize(example);

(Sorry if there are syntax errors the code was just typed by hand)

I won't know what type the XML is going to have at design time but I will never need to access the Example property programatically - I just need it to appear in xmlText.

Thanks,

Joe