These days a similar product, still called finnan haddie, is smoked in New England over hard wood.
From the boston.com
Finnan haddie is often served poached in milk for breakfast.
From the en.wikipedia.org
Word is, when Locke-Ober finally does start serving lobster stew and finnan haddie again, it is likely to be without chef Lydia Shire, who famously revamped the downtown landmark back in 2001.