Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1      Package       yellow cake mix
   3      Ounces        vanilla pudding -- instant
   1      Cup           water
     1/3  Cup           vegetable oil
   3                    eggs
   1      Teaspoon      salt
                        FILLING:
   5      Tablespoons   flour
   1      Cup           sugar
     1/2  Cup           shortening
   1      Cup           water
     1/2  Cup           Margarine
   2      Teaspoons     vanilla

Preparation:

Mix cake mix, pudding, water, oil, eggs and salt. Pour into waxed paper lined 9X13" pan. Bake at 350° for 35-40 minutes. Cool. Remove cake from pan and slice lengthwise with a thread. Combine flour and water. Cook until thick. Cool. combine sugar, margarine, shortening and vanilla. Beat until thick and fluffy. Add this to the cooled flour mixture. Sread filling mixture on one half of cake top with other half of cake.