What is the correct way to use JSON.NET to parse stream of JSON objects?

I think if you change your loop around slightly everything should work:

public IEnumerable<TResult> ReadJson<TResult>(Stream stream)
{
    var serializer = new JsonSerializer();

    using (var reader = new StreamReader(stream))
    using (var jsonReader = new JsonTextReader(reader))
    {
        jsonReader.SupportMultipleContent = true;

        while (jsonReader.Read())
        {
            yield return serializer.Deserialize<TResult>(jsonReader);
        }
    }
}

Note that you must iterate over the IEnumerable<TResult> while the Stream passed to this method is open:

using (var stream = /* some stream */)
{
    IEnumerable<MyClass> result = ReadJson<MyClass>(stream);

    foreach (var item in result)
    {
        Console.WriteLine(item.MyProperty);
    }
}

Example: https://dotnetfiddle.net/Y2FLuK

Sample on JsonNet site: Read Multiple Fragments With JsonReader