pot luck

1. N-COUNT A potluck is a meal that consists of food brought by the people who come to the meal, or a meal that consists of whatever food happens to be available without special preparation. 百家饭; 大杂烩[美国英语] [oft N n]

The event will kick off with a potluck. 该活动将以吃一顿百家饭启动。

If they drop by, I'll make a potluck supper. 如果他们顺访这里，我就做一个大杂烩当晚饭。