Lemon Icebox Pie Filling

Whisk together 3/4 cup milk and 1/4 cup cornstarch in a 3-quart heavy saucepan, whisking until cornstarch dissolves.

Whisk in sweetened condensed milk and eggs until blended; whisk in lemon juice and, if desired, food coloring. Bring to a boil over medium heat, whisking constantly. (

Mixture will begin to thicken when lemon juice is first added, and then become thin again during first few minutes of cooking. It will thicken quickly as it comes to a boil.)

Boil 1 minute, whisking constantly, or until mixture thickens.

Remove mixture from heat, and whisk in butter and lemon rind until smooth.

Pour filling into a large bowl, and place bowl in a larger bowl filled with ice. Stir regularly until cold (about 10 minutes).

Lime Icebox Pie Filling: Substitute 1/2 cup fresh lime juice for lemon juice, 1 drop green food coloring and 1 drop yellow food coloring for the 3 drops yellow food coloring (optional), and 1 tablespoon grated lime rind for lemon rind.

Orange Icebox Pie Filling: Substitute 1/2 cup thawed frozen orange juice concentrate for fresh lemon juice, 2 drops red food coloring and 4 drops yellow food coloring for 3 drops yellow food coloring (optional), and 1 tablespoon fresh grated orange rind for lemon rind.