When I select 'recipes' on my book shelf, I can see 'Add multiple bookmarks'. However, if I select a book, the option to add multiple bookmarks to recipes within that book disappears. Am I doing something wrong?
Bookmarks are a function of your Bookshelf. When you click a book title it opens the book in the Library. So in order to add bookmarks just to one book, enter the book title in search when in your Bookshelf. Now you can add the bookmarks to every recipe in the book.