Here is one of my favorites, an old recipe from the 17th Pillsbury Bake-Off in
the 1960's.

PLUM FUN CAKE

1 1/2 cups flour
1 cup sugar
1 teaspoon baking soda
1 teaspoon baking powder
1/2 teaspoon salt
1/2 cup cold water
1/2 cup chopped walnuts
1/3 cup seedless raisins
1/3 cup cooking oil
1 tablespoon vinegar
1 teaspoon vanilla extract
1 egg
4 3/4-ounce jar strained plums baby food (reserve 1 tablespoon for icing)

In 9-inch square pan, combine flour, sugar, baking soda, baking powder and salt.
Add remaining ingredients. Stir vigorously with rubber scraper for 1 minute.
Bake at 350 degrees for 30 to 35 minutes or until cake springs back when lightly
touched in center. Cool; frost.

ICING
1 tablespoon strained plums
2 cups confectioners' sugar
1/4 cup softened butter
1/2 teaspoon vanilla extract
Dash of salt

Combine all ingredients; beat until of spreading consistency. If necessary, thin
with a few drops of water.