Preheat oven to 325 degrees. Beat egg whites until stiff. Beat egg yolks slightly and mix well with sugar. Add ground almonds and lemon rind. Fold in egg whites. Grease and “flour” an 8-inch springform pan with matzoh meal. Pour in batter. Bake for one hour.
Glaze: Ten minutes before the cake is done, beat the yolk, juice, sugar and rind in a saucepan. Boil, stirring constantly until it thickens, about five minutes. Stir in butter. Poke holes in the top of cake with a toothpick. When cake has cooled just slightly, while still in springform pan, pour on glaze. Let it stand for a few minutes before removing the cake. Serves 12.