Stephen, 43, and Karen Lennie, 42, created the world's first chocolate that doesn't melt and have now sold it all over the world.
They came up with the idea for flexible Magic Choc at their kitchen table in Belfast to keep their daughters Rebecca, Natalie and Aimee amused on rainy days.
Stephen said: "I created it on a paper plate at the kitchen table but the kids loved it. They wanted to play with it every day so we knew it was going to be a big success."
The patented recipe includes a special ingredient which means the treat can be moulded into any shape but stays bendy when set. The chocolate stays pliable from 20°C and can be moulded in temperatures up to a scorching 37°C. It lasts for 18 months.
Because it doesn't melt so there is no mess to clean up.
Packs of the £4.99 Belgian-style chocolate are manufactured in the UK and the firm has just taken on extra staff to cope with the demand.
Toy expert Paul Jackson from TheInThing.com said: "Magic Choc has amazed us all. Sales have literally gone through the roof."