I know that one of mine definitely has. I didn't think it was possible, but she's a hen that I found and rescued so she is isolated in her own separate cage with no other hens who could have laid the extra egg. She usually lays an egg every other day, and every once in a while will lay two days in a row. One day I came home after dark and checked the cage as usual because it was an 'egg' day for her, but there was no egg. I thought it was weird because she always lays an egg at least every other day and there had been no egg the day before. The next day there were TWO eggs in there.
There's nowhere that an egg could have hidden, the cage is just a 24 by 36 dog kennel and I checked it thoroughly.
I believe it is rare but yes a chicken can lay 2 eggs in one day. I seen my one Red Sex Link do it. There was no eggs in the nest, she layed one egg I got that one out and she laid another egg right after thr first. Good chicken. LOL.
, just kidding, but along the same lines as a double yolker, some hens are just a little better at spitting out them eggs than the rest of the girls. You got you one thats a show off...
I have a friend who I sold 15 White leghorn hens to and she gets up to 20 eggs a day from them alone. I suppose that during a certain time of year I suppose they lay extra.