This is a creamy citrus filling. If you want a stronger flavor, use 1 tablespoon lemon juice, 3 tablespoons orange juice, and 1 teaspoon grated orange rind.
1 Combine sugar and flour in a saucepan. Add water gradually, stirring constantly. Slightly beat the egg and yolk, and add with butter, lemon juice, and orange juice to the saucepan. Mix well. Cook and stir over medium heat until mixture comes to a boil and is thickened – about 7 minutes. Cool before spreading on cake.