"It was a sort of a weird brain child of confectionary and technology," explained Middleton on CNBC's "Closing Bell."
And it works best with lighter images without too much detail.
Middleton added that although the product may seem unexpected, he had worked in the bakery industry for years and Boomf is the evolution of his efforts over time.
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And now, the younger brother of the Duchess of Cambridge is bringing his specialty confection to the U.S., with a box of nine marshmallows featuring a photo uploaded to his website from Instagram or Facebook or straight from your computer costing $25. "It's free shipping anywhere in the world," Middleton added.
And if you're in London, according to the website, these so-called "magical mallows" are sold inside the famed department store, Selfridges & Co.