3
Meanwhile, in medium saucepan, combine 1 cup sugar and cornstarch; mix well. Gradually stir in lemon juice until smooth. Cook over medium heat, stirring constantly, until mixture boils; boil 1 minute, stirring constantly. Remove from heat. In small bowl, beat egg yolks; stir about 2 tablespoons hot mixture into egg yolks. Gradually stir yolk mixture into hot mixture. Cook over low heat, stirring constantly, until mixture boils. Boil 1 minute, stirring constantly. Remove from heat; stir in lemon peel and food color. Cover surface of filling with plastic wrap. Cool 45 minutes or until completely cooled.