Lammas/Lughnasadh occurs every year on August 1st. It is the first of three harvest holidays and is appropriately dubbed The Feast of First Fruits. The name says it all. This is a celebration of abundance. We celebrate with breads of all sorts, as they have always been a symbol of prosperity.
Special foods for the day include bread and berries of all sorts. Drinks included in your feast should be beer, wine, and cider.
Source: Trace of Dawn