Quote from : The Time Traveller's Guide to Medieval England: A Handbook for Visitors to the Fourteenth Century Book

You might be offered oatcakes as well as bread (especially in the north). If these do not tempt you, consider eating "horse-bread." This is made from a sort of flour of ground peas, bran, and beans–if contemporaries look at you strangely, it is because it is not meant for human consumption.