The egg weighed a hefty 170 grammes, which is a staggering 113 grammes heavier than the average 57 gramme-egg.
Couple Steve and Annie Egginton from Chew Magna, Somerset, were amazed when they saw what their one-year-old white Sussex hen Jessica had produced.
The egg was laid on the opening day of the Olympics, which also happened to be Annie's 59th birthday, the Daily Mail reported.
Steve, 60, said that despite keeping chickens for more than three decades he has never seen anything like it.
"I've been keeping chickens for about 30 years now and I have never seen an egg this big," he said.
"We've got three hens at the moment, all of them laying around two eggs a day, but they've never laid an egg like this before," he added.
The couple, who have three chickens, Jessica, Doris and Henryetta, say they have always produced eggs for themselves and their family members.
Instead of keeping the giant egg, thought to be the "world's largest egg", they have since tucked into the extra large produce for breakfast.
"We used the egg to make scrambled egg on toast for the both of us for breakfast. It was very tasty and a rather substantial meal for us both," Steve added.
Despite the monster weight of the egg it is not quite heavy enough to break the Guinness World Record for the largest hen egg, which currently stands at a staggering 453.5 grammes.
