These are delicious and can be made ahead of time without losing their freshness. I borrowed the recipe from the Mitford Series Cookbook - these are Cynthia's Lemon Squares! :)
2 cups flour
1/2 cup plus 2 to 4 Tablespoons powdered sugar
1 cup plus 2 Tablespoons unsalted butter
1 teaspoon vanilla
1/4 teaspoon plus 1/8 teaspoon salt
2 cups sugar
2 Tablespoons cornstarch
5 large eggs - at room temperature
zest from 1 lemon
fresh lemon juice from 1 lemon
Preheat oven to 350 degrees. Grease a 9x13 baking pan with nonstick cooking spray
In mixing bowl, mix together flour, 1/2 cup of the powdered sugar, 1 cup of the butter, the vanilla, and 1/4 teaspoon salt on medium speed until combined. Pat the batter into the pan and bake for 18 minutes, or until a light gold color.
Melt the remaining 2 tablespoons butter in a small saucepan over low heat. Set aside to cool slightly.
Meanwhile, in the mixing bowl, combing the sugar and cornstarch. Add eggs, one at a time, beating well after each addition. Add lemon zest and juice, 1/8 teaspoon salt, and melted butter; beat well. Pour the lemon mixture over the crust and bake for another 20-25 minutes, or until set.
Let cool completely, then sift remaining powdered sugar over the lemon squares. Chill and cut into squares.