I found this David Chang Ranch Recipe in this online article: https://www.gq.com/story/david-chang-summer-snacks
Apparently not the same one as in Momofuku.
But I persevered and finally found the Ramp Ranch Dressing Recipe here: https://books.google.com/books?id=hPWiQZt5aRcC&pg=PT354&lpg=PT354&dq=david+chang+ramp+ranch+dressing&source=bl&ots=Ar4u_SMx3l&sig=ACfU3U2GBdsfVoFFIx3d_RXeOQ6mxUAsZw&hl=en&sa=X&ved=2ahUKEwj57-W_mKPlAhVQJt8KHSC4CI4Q6AEwBnoECAoQAQ#v=onepage&q=david chang ramp ranch dressing&f=false