Exactly what it sounds like.
Make sure to know in advance what your cooking facilities are. Things can be prepared elsewhere and brought if timing and temperature allow.
You can expect your attendees to have widely varying skills and confidence regarding cooking. Be prepared to give some people supporting roles.
It is likely wise to have a central point of co-ordination and to do some planning. This way, you don’t have five desserts and no main course (unless, of course, you want that) or three dishes that need to be baked at different temperatures at the same time in only one oven.
We don’t really have traditional solstice foods, though things requiring long preparation or low-tech preservation have been proposed.
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