Bind to arbitrary Dictionary<,> by using a converter to cast object

I'm trying to workaround the difficulties in binding to a Dictionary in WinRT Xaml (also referenced here). I want to use a converter to do this rather than having to change all of my view-models or business code to return a List of a custom Key Value class.

This means I need to cast an object to a List<> of some type.

    public object Convert(object value, Type targetType, object parameter, string temp)
    {
        if(value is IDictionary)
        {
            dynamic v = value;

            foreach (dynamic kvp in v)
            {

            }
        }
        return //some sort of List<>
    }

I don't know how to do this though. When I mouse over the value in the debugger it still remember its appropriate type (like Dictionary) but I don't know how to make use of this at run time.

What do I need to do to cast something of type object (which is guaranteed to actually be a Dictionary<,>) to some sort of List so that I can bind to it in XAML?