Grandma's Best Classic Lemon Meringue Slice

Preheat oven to 350 degrees F.

Combine the biscuit crumbs and melted butter, mix well. Press onto the bottom of an 8x8 inch baking pan. Bake for 10 minutes, or until lightly browned. Let cool.

Meanwhile, in a medium saucepan, combine 1 cup sugar, flour, cornstarch, and salt. Gradually stir in water and lemon juice, until the mixture is smooth. Bring to a boil, reduce heat, and simmer for 2 minutes, stirring constantly.

Remove from heat and stir in lemon zest and butter. Slowly pour half the lemon mixture into the egg yolks, whisking constantly. Once incorporated, pour the egg yolk mixture back into the saucepan, bring back to a boil, then reduce heat and cook for 2 more minutes. Pour over the prepared crust.

In a large glass or metal bowl, whip egg whites until soft peaks form. Gradually add sugar, beating until stiff peaks form. Spread meringue carefully over the lemon filling, sealing the edges.

Bake in the preheated oven for 10 minutes, or until golden brown. Let cool, then refrigerate before slicing.