Red Velvet Cake

Red Velvet Cake
Cake:
2 1/2 cups sifted cake flour
1/2 tsp. salt
3 tbsp. chocolate-flavored drink mix
1/2 cup solid shortening
1 1/2 cups granulated sugar
2 eggs
2 oz. red food coloring
1 tsp. vanilla extract
1 cup buttermilk
1 tbsp. white vinegar
1 tsp. baking soda
Mystery Icing:
4 tbsp. flour
1 cup milk
1 cup sugar
1 stick butter
1/2 cup vegetable shortening
Dash of salt
1/4 tsp. vanilla extract, or more, to taste
To make cake, sift together flour, salt and chocolate-flavored drink mix. Cream together the shortening and sugar. When mixture is well creamed, beat in eggs one at a time. Blend well and add food coloring and vanilla. Mix buttermilk, vinegar and baking soda. Add alternately with dry ingredients to the creamed mixture. Blend, at low speed of electric mixer, between each addition.
Grease and flour two 9-inch cake pans (or grease and line with greased parchment paper). Pour in batter and bake in preheated 350-degree oven about 30 minutes or until done. (Cake will rise high.) Do not overbake. Remove from pans and cool on racks before frosting.
To make icing, blend flour and milk in saucepan. Cook until mixture thickens to consistency of cream. Cool but do not chill. Cream sugar, butter and vegetable shortening, adding salt and vanilla. Add the slightly cooked flour mixture and continue beating until very fluffy. Spread between cake layers and over top and sides of cake.