Nagasaki Castella

Preheat your oven to 160 degrees Celsius. Line a square or rectangular baking pan (approximately 18cm x 18cm or 20cm x 10cm) with parchment paper, ensuring the paper extends above the pan sides.

Combine the Honey, Mirin, Water, and Salt in a small heatproof bowl. Gently warm the mixture over a hot water bath or in a microwave until the Honey is fully dissolved and the mixture is warm, then set aside.

In a large heatproof bowl, combine the Whole eggs and Granulated sugar. Place this bowl over a pot of simmering water (bain-marie), ensuring the bottom of the bowl does not touch the water. Whisk continuously with a hand mixer on medium speed until the mixture reaches approximately 40 degrees Celsius and is warm to the touch. This process helps the eggs emulsify and incorporate more air.