Faggots have long been a staple of English cuisine. As a very down to earth dish, made from the remnants of butchery, it is perhaps understandable that here they are made to sound more fancy by calling them “Belgian,” though there is nothing in the recipe to suggest that there is anything foreign about them.
Calling any food item a “faggot” now would probably seem to many to be particular unsavory, given the more contemporary and derogatory use of the word to describe homosexuals. Neither of these two terms have any connection to the other faggot — that of a bundle of sticks, which has been a term in use since the 13th century.
A Plain Cookery Book for the Working Classes, Charles Elmé Francatelli, The Scolar Press, 1852