Double-shelled eggs are so rare that even though there are videos of people cracking them open, many people are convinced they are not real.

The process occurs when “an egg that is nearly ready be laid reverses direction and gets a new layer of albumen covered by a second shell,” reports Poultry Help.
According to Countryside Network, the process that causes the egg to reverse is called a ‘counter-peristalsis contraction’.
However, there is this YouTube video of a man who describes himself as “just an old Texas farmer appreciating nature” discovering a huge egg laid by an average sized chicken. The video was uploaded in July 2015, and so far, it has been seen more than 3 million times.

The farmer starts tapping the egg and makes a small crack in the shell. He then peels off one small part and we can clearly see the yolk.

“Oh, I see another surprise!” he says with a chuckle.
“A double egger!”

The farmer slowly pours the yolk out of the shell, until only the inner egg remains. He says, “No double yolks, that’s for wimps. We got double eggs!”

The second egg which was inside the big one is with a regular size. He cracks that one too, and it’s just a plain egg, like those we buy at the grocery store.