Sponge Cake

Directions

1. 1
   Beat the egg yolks with about half the sugar, till thick and very pale, then stir in the lemon zest.
2. 2
   Beat the egg whites stiff with the salt.
3. 3
   Add the remaining suger and beat to a very stiff, shiny meringue.
4. 4
   Then fold in the yolk mixture.
5. 5
   Sprinkle the flour on top and very gently fold in as lightly as possible.
6. 6
   Turn into a deep, oiled, nonstick spring form cake pan about 9 inches (23 cm) in diameter and bake at 350F (180C) for about 1hour, until browned on top.
7. 7
   VARIATION:
8. 8
   You may add 2 or 3 drops of vanilla extract to the yolk mixture.