Chiffon cake combines the cloudlike texture of angel food cake with a tender richness provided by egg yolks and oil. It can be flavored with citrus, chocolate, vanilla, or any flavoring you chose. It's usually served with a light dusting of confectioners' sugar or whipped cream; heavier buttercream frostings tend to weigh it down.
Chiffon cakes may be baked either in tube (angel food) pans, or in 9" round cake pans. Like an angel food cake, they must be cooled upside down to maintain their full height. This recipe makes a large cake, enough for 16 to 20 slices. It also freezes well, and is a good base for any filled cake that's served cold, because the use of oil lets it retain its soft texture in the fridge.