Newspaper mold: Stack 6~7 sheets of newspaper together. Fold into a triangle, and cut off the rectangle sticking out.
Make a 17 cm crease from each edge, and cut a notch into the 4 areas (along the lines).
Fold into the 17 cm crease.
Tuck in the corners, straighten the edges to form a box, and secure with a stapler.
Spread out a sheet of aluminum foil first.
Spread out another sheet from another direction while taking care not to rip the corners (the batter will become difficult to remove from the mold if you do).
For the castella: sift the bread flour.
Preheat an oven to 320F/160℃.
Divide the egg yolk and white, and whisk the egg whites.
After whipping the meringue to stiff peaks, add 1/3 of the sugar, and whip again.
Add 1/3 of the remaining sugar, whip, add the remaining 1/3 sugar, and briskly whip.
Add egg yolks to the well-whipped meringue, and stir.
After stirring together, add vegetable oil and milk, and mix in.
Add flour in 3 separate batches and mix in after each addition, pour the mixture into the mold, and bake at 320F/160℃ for 70 minutes.
After it has finished baking, remove immediately from the mold, wrap the entire castella in plastic wrap, and let it sit for a while.
It is done once it has cooled.
Story Behind this Recipe
This is how my mother always makes castella. It is surprisingly simple and delicious.
-When whipping in Steps 10 and 11, it is important to continuously and thoroughly whip it! -When wrapping in plastic wrap in Step 15, the castella will become moist. -I let this cool for about 2 hours before eating, but it is even better if you let it sit overnight!