Here's what I've read from copyright.gov
"Copyright law does not protect recipes that are mere listings of ingredients. Nor does it protect other mere listings of ingredients such as those found in formulas, compounds, or prescriptions. Copyright protection may, however, extend to substantial literary expression—a description, explanation, or illustration, for example—that accompanies a recipe or formula or to a combination of recipes, as in a cookbook.
Only original works of authorship are protected by copyright. “Original” means that an author produced a work by his or her own intellectual effort instead of copying it from an existing work.
For further information about copyright, see Circular 1, Copyright Basics. Note that if your recipe has secret ingredients that you do not want to reveal, you may not want to submit it for registration, because applications and deposit copies are public records.
Deposit requirements depend on whether a work has been published at the time of registration:
If the work is unpublished, one complete copy
If the work was first published in the United States on or after January 1, 1978, two complete copies of the best edition
If the work was first published outside the United States, one complete copy of the work as first published
If the work is a contribution to a collective work and was published after January 1, 1978, one complete copy of the best edition of the collective work or a photocopy of the contribution itself as it was published in the collective work
FL-122, Reviewed December 2011"
Further, I've found
"One should distinguish between a recipe, a textual rendering of a recipe, and a compilation of recipes. Publications Intl. v. Meredith, 88 F.3d 473 (7th Cir. 1996) dealt with alleged infringement of a recipe book.
“The identification of ingredients necessary for the preparation of each dish is a statement of facts. There is no expressive element in each listing; in other words, the author who wrote down the ingredients for “Curried Turkey and Peanut Salad” was not giving literary expression to his individual creative labors. Instead, he was writing down an idea, namely, the ingredients necessary to the preparation of a particular dish. “[N]o author may copyright facts or ideas. The copyright is limited to those aspects of the work–termed ‘expression’–that display the stamp of the author’s originality.” Harper & Row, 471 U.S. at 547, 105 S.Ct. at 2223. We do not view the functional listing of ingredients as original within the meaning of the Copyright Act.
As the Supreme Court stated in Feist: Facts, whether alone or as part of a compilation, are not original and therefore may not be copyrighted. A factual compilation is eligible for copyright if it features an original selection or arrangement of facts, but the copyright is limited to the particular selection or arrangement. In no event may copyrights extend to the facts themselves. Feist, 499 U.S. at 350-51, 111 S.Ct. at 1290."
Has your friends recipe been published? No? Then it's fair game.
I can say to you that I have such a recipe, handwritten on a lovely recipe card, and I have been sworn to secrecy; that I should never tell anyone else how I've made it... basically, for my eyes only! And I've kept it that way for, oh, over 40 years now and it's one of my most requested cakes.
So, in closing giggler aka Eric in Austin, it's always nice to ask the individual how has given you a recipe if it's okay to share that said handwritten recipe with the Internet world or not.