4 egg whites
1/2 cup lemon juice
1 teaspoon vanilla extract
1 cup hot water
2 1/4 cups all-purpose flour
1 teaspoon baking soda
1 teaspoon ground cinnamon
1/2 teaspoon salt
Preheat the oven to 350 degrees F (175 degrees C). Grease and flour a 9 inch pan.
Beat eggs until foamy. Mix lemon juice and vanilla extract into lemon mixture. Stir in hot water and flour. Mix together. Pour batter into prepared pan.
Bake in the preheated oven for 1 hour. Cool cake completely before removing from pan.
In a large bowl, combine lemon juice, lemon zest and lemon zest. Stir lemon zest mixture into lemon filling. Pour mixture over cooled cake. Chill overnight; serve immediately.