Sunday's are Chocolate

I have not made this cake for years the unique thing about this cake is the different flavors of the icing. I just used one chocolate cake mix, and cut each layer in half. If I were making this again I would double the icing recipe. I used butter instead of the shortening. Each bite is a different flavor. I am sure it would taste the same with your favorite icing recipe. This icing is smooth and creamy it does not appear to harden up like some I have tried.
Rainbow Frosting

1 cup milk
2 tablespoons flour
Pinch of salt
1/2 cup butter room temperature
1/2 shortening room temperature
1 cup granulated sugar
2 to 3 drops green food coloring
1/4 teaspoon almond flavoring
2 to 3 drops yellow food coloring
1/4 teaspoon lemon flavoring
2 to 3 drops red food coloring
1/4 teaspoon peppermint flavoring
3 table spoons cocoa
1/4 teaspoon vanilla

In a small sauce pan, combine milk, flour and salt. Cook over medium heat about 5 to 7 minutes, until thickened. Cool. Combine butter or margarine, shortening and sugar in a medium bowl. Beat well. Add to cooled milk mixture, beating constantly. Beat about 7 minutes, until smooth. Divide mixture among 4 bowls. In the first bowl add yellow food coloring and lemon flavoring. In the second bowl, add green food coloring and almond flavoring. In the third bowl, add red food coloring and peppermint flavoring. Add cocoa and vanilla to the fourth bowl.