You can add any online recipes to the EYB LIbrary using the Bookmarklet, explained here in Help. Some sites put up blocks against data scraping so I tested this site and the import worked well (apart from the photo not importing but Nikki will deal with that when she approves the recipe addition).
There are 36 National Trust online recipes already in the Library, some as links from recipes in National Trust cookbooks, some as Bookmarklet imports, and some where other cooks such as Ottolenghi reproduced their recipes.