Matcha Castella

1. Preheat your oven to 160°C (325°F). Line a rectangular baking pan (approximately 20x10 cm or 8x4 inches) with parchment paper, ensuring the paper extends above the sides of the pan to support the cake's rise.

2. In a large heatproof bowl, combine the whole eggs and granulated sugar. Set the bowl over a pot of simmering water (bain-marie) and whisk constantly until the mixture is warm to the touch (around 40°C / 104°F) and the granulated sugar has fully dissolved.

3. Remove the bowl from the heat. Using an electric mixer, whip the egg mixture on high speed for 10-15 minutes until it becomes very pale, thick, and forms a stable ribbon when the whisk is lifted. The volume should approximately triple.