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It’s led to raids by law enforcement agencies and mass deaths in animals; in the United States, chefs have ‘dealers’ who smuggle it into the country.

Given these facts, I’m unwrapping my online delivery with a level of suspicion usually reserved for bomb disposal. Inside is a jar of wrinkled black beans, each resembling an elongated raisin. These are ‘tonka beans’ – the aromatic seed of a giant tree from deep in the Amazon rainforest.

When grated into desserts or infused into syrups, they impart a flavour so transcendent, tonka has been dubbed the most delicious ingredient you’ve never heard of.

Notes of freshly cut grass mingle with vanilla, liquorice, caramel and clove, topped off with a suggestion of warmth and a hint of magnolia – that is, according to the internet. I unscrew the lid and take a whiff. They smell faintly like furniture polish.