In the following fatwa -see here in Arabic- sheikh ibn Baz quotes a hadith -which seems familiar to me- saying that during the battle of al-Ahzaab the sahabi Jabir ibn 'Abdullah al-Ansari () جابر بن عبدالله الأنصاري invited the Prophet () for a meal of small dhabihah and some cereals -if I re´member the incident well he intended only to feed the prophet () as the meal was simple and "small"- the prophet () then ordered to cut the bread and the flesh and then called in ten sahabah by ten who ate and drank and stilled their hunger then left, while ten more entered and ate etc.
Even if the story is well known I guess I read about it in some seerah books. I don't know the source and was not really able to find it and whether it appears in hadith compilations.
I hope you could provide me some sources!
A qualification of the source would be appreciated!