Line the pound cake molds with parchment paper, smoothing out any wrinkles. Sprinkle with a layer of crystal sugar on the bottom.
Whisk the egg whites, while gradually adding the sugar a little at a time. Mix until thick and shiny.
Add the egg yolk and mix lightly.
In a separate bowl, combine the condensed milk, honey, milk and oil and mix until even. Add to the bowl from Step 3.
Sift the already sifted flour into the mixture with a spatula.
Once the flour is incorporated, gently fold the batter from the bottom several times.
Pour the batter into each mold. Tap the molds slightly to even the surface.
Bake for 25 minutes in preheated oven at 320°F/160℃. Once baked, flip them over on a sheet of parchment paper.
Quickly wrap tightly in plastic wrap and leave them for 2 days at room temperature. You can serve them the following day, but they're best served two days after baking.
Slice the castella into cm thickness, and cut each slice in half. Arrange on a baking sheet and bake for 15 minutes in 285°F/140℃. Let sit in the oven for 15 minutes.
Cool on a cake rack. They will be crispy and delicious. Once cool, wrap for gifting.
Story Behind this Recipe
After talking with my father about castella, I had a craving for some. I checked a cooking book, but since the recipe was different from what I wanted, I adjusted it to come up with my own.
All of the ingredients must be brought to room temperature. Whisk the egg white well. After adding flour, mix evenly, but do not mix too much. It's best to serve 2 days after baking. The first day is too fluffy. For best results, the parchment paper should be smooth, without any wrinkles.