Twinkie Cake

1 (18.25 ounce) box white cake mix
1 small box vanilla instant pudding
1/2 cup vegetable oil
3 eggs
1 cup milk
1/2 teaspoon salt
1/2 cup margarine, softened
2 teaspoons vanilla extract, divided
4 tablespoons flour
1 cup granulated sugar
1/2 cup white Crisco
1 cup water

Combine cake mix, oil, eggs, pudding and water and 1 teaspoon vanilla extract. Beat at medium speed for 2 minutes. Pour into a greased and floured 9 x 13-inch pan.

Bake at 350 degrees F for 40-45 minutes or until cake tests done.

In a saucepan mix the flour with the milk. Cook until thick, stirring constantly; cool.

Add sugar, salt, Crisco, margarine and remaining 1 teaspoon vanilla extract. Beat until fluffy. Spread on the cooled cake. Store in refrigerator.