In this situation, the waiter omit a word "fan cai(饭菜 food)"in oral Chinese. Its full expression is "ni dian de fan cai huo shi wu lai le"(你点的饭菜或食物来了,Your food is coming)
le pronounce fifth tone,no problem.
lai means come. For example, if you meet a colleaque at office in the morning ,you can say 你来了(ni lai le)to say hello.