Sour Orange Pie

3/4 cup plus 3 tablespoons granulated sugar
3 level tablespoons cornstarch
1 cup hot water
1 tablespoon butter
3 eggs, separated
1/3 cup sour orange juice
1 baked 9-inch pie shell

Preheat oven to 375 degrees F. In a saucepan, mix together the 3/4 cup sugar and cornstarch, and slowly pour in the hot water and butter, stirring to dissolve any lumps. Beat egg yolks lightly and add, along with the sour orange juice. Stir constantly over medium-low heat until the mixture has thickened and coats the spoon. Do not boil. Carefully pour the filling into the baked pie shell.

For the meringue, beat the egg whites until frothy. Continue to beat, gradually adding the 3 tablespoons sugar, until the beater holds stiff peaks when lifted. Gently swirl the meringue over the filling, making sure it touches the edges of the crust all the way around. Bake until the meringue is brown. Remove from the oven and cool on a rack.