It was a spring day in 1200s Japan, with cherry blossoms in bloom and picnics unfolding beneath the delicate pink petals. Amid the celebrations, legend has it that a nobleman brought along an unconventional snack – boiled eggs with salt. Since a ban by the Emperor in 675 AD eating meat was prohibited.

When the influence of Portuguese traders began to shift culinary traditions in Japan, eggs found their way into the diet. By the 18th century, egg peddlers appeared, who would carry eggs in a bucket on a pole and hawking 'tamaaago, tamaaaaago' (eeeeeggs, eeeeggs!). In 1785, the first egg cookbook – Tamago Hyakuchin – appeared, describing how to cook 103 different egg dishes.

Today, eggs are a beloved staple in Japanese households, with Japan ranking as one of the top egg consumers in the world. The nation has created an impressive array of cult-classic dishes centred around this humble ingredient. Onsen tamago: a luxurious condiment If you'll excuse me, it's time for a snack.

Credit: Camellia Aebischer Thanks to Japan's numerous onsen (hot springs), locals have used these natural jacuzzis as giant saucepans for centuries. The spin that this method puts on the boiled egg is part nutrients from the waters, part novelty, and part science – eggs are slow-cooked at temperatures between 65°C and 70°C, resulting in a soft and silky egg white and custardy yolk. Onsen eggs are served atop a bowl of rice, pasta, salad, even as a dipping sauce for sukiyaki , adding its characteri.