Queen Elizabeth II loved chocolate, and though England is home to some famous chocolatiers, none can claim to use exclusively domestic ingredients, nor do any produce a 100% British chocolate bar. However, confectioner Rowntree pulled off a small miracle at one time by managing to grow cacao beans in the country.

In 1932, Rowntree factory workers who had been experimenting with growing pineapple plants in a hothouse decided to try planting a cacao tree. The tree grew successfully, but it produced only one cacao pod that had just enough seeds to make a tiny chocolate bar, and naturally, the bar went to one of England's most beloved figures.

The rare chocolate bar was given to the King's daughter, Elizabeth, who at the time was titled Princess Elizabeth of York. She consumed possibly the rarest chocolate the world has ever seen, being the only 100% British chocolate to ever exist — perhaps this could be why the queen had such an affinity for the sweet treat.