With orange zest in the filling.
From the box of A.D. from Lutz, Florida, by way of Pennsylvania in the 1940s, and originating in Ohio in the 1920s.
Chocolate Layer Cake
[Ingredients:
1 cup sugar
1 egg, beaten
1 cup milk
1-3/4 cups flour
1/4 tsp. salt
4 tsp. Royal baking powder
1 tsp. vanilla
Filling:
3 cups confectioner’s sugar
1 tsp. vanilla
2 oz. unsweetened chocolate, melted
1/2 tsp. grated orange peel]
Cream 1/2 cup shortening with 1 cup sugar, beating well; add 1 beaten egg, 1 cup milk slowly, and mix well. Add 1-3/4 cups flour sifted with 1/4 teaspoon salt and 4 teaspoons Royal Baking Powder; mix in 1 teaspoon vanilla, bake in 3 greased layer cake tins in moderate oven, 15 or 20 minutes.
Filling: 3 cups confectioner’s sugar. Add slowly boiling water to make smooth paste. Add 1 tsp. vanilla, 2 oz. unsweetened melted chocolate, 1/2 tsp. grated orange peel.