1 (18.25 ounce) package lemon flavored Jell-O
1 cup boiling water
1 cup lemon liqueur
2 cups cornstarch
1 cup boiling water
1/2 cup white sugar
1/3 cup lemon juice
1 teaspoon lemon zest
3 cups unsalted butter, melted
5 egg whites
1 tablespoon lemon zest
2 teaspoons lemon zest
1 teaspoon vanilla extract
4 egg whites
In a large bowl, mix boiling water, lemon liqueur, cornstarch, boiling water, sugar, lemon juice and lemon zest. Stir with wire whisk until the mixture is smooth and just moist.
Mix melted butter into the creaming mixture with a spoon, beating until the batter is smooth. Gently mix egg whites, then pour into a separate bowl. Stir egg white mixture into the batter.
When the batter has firmized, pour into crust. Cover with foil and chill overnight.
Preheat oven to 350 degrees F (175 degrees C). Bake in preheated oven for 15 minutes. Remove foil and bake for 30 minutes. Cool completely. Cut into triangles.