Sponge Cake: Heat oven to 325 degrees F. Use a 12-inch tube pan.
Sift flour with baking powder.
Separate eggs, putting whites in large bowl of electric mixer, yolks in
next size bowl.
Beat whites at high speed until frothy, then sprinkle in the cream of tartar
and continue beating until whites stand in peaks but still cling to the side
of the bowl (takes about 3 minutes).
Add 1/2 cup sugar very gradually, still beating at high speed, until you
have a smooth, satiny meringue. Set aside.
Beat yolks at high speed for 2 minutes.
Pour in the orange juice, beating for 1 more minute, still at high speed.
Add remaining sugar very gradually to yolks; add salt and vanilla extract
and continue beating until mixture looks light and smooth. Remove from mixer
and fold flour into egg yolks until batter is smooth. Do not beat. Pour this
batter into the meringue and fold batter very gently again until all patches
of egg white disappear.
Pour into ungreased tube pan and bake 1 1/4 hours.
Cool, upside down on a rack, for one hour, then pull cake carefully away
from pan with your hands.
When cool, cover with confectioners' sugar or Pineapple Glaze.
Pineapple Glaze: Melt butter.
Beat egg yolk for 1 minute at high speed of electric mixer. At low speed,
pour in melted butter, crushed pineapple, pineapple juice, lemon rind and confectioners'
sugar. Beat for 2 minutes.
Spoon this thin glaze over top of cake allowing some of it to trickle over
the cake sides.