1/2 cup margarine, softened
1/4 cup granulated sugar
1/4 cup light brown sugar
1/2 teaspoon vanilla extract
1 egg yolk
1/2 cup sifted flour
1/2 cup rolled oats

Cream margarine and sugars. Add vanilla extract and egg yolk and beat until light. Stir in flour and oats and pour into a greased 8-inch square baking pan and bake 25 to 30 minutes at 300 degrees F. Ice when cool.

Makes 16 squares.

Icing
2 (1 ounce) squares unsweetened chocolate
1 1/2 tablespoons margarine
1 1/2 cups confectioners' sugar
Pinch of salt
3 1/2 tablespoons milk
1 1/2 teaspoons vanilla extract

Melt chocolate and margarine in double boiler. Turn off heat and add remaining ingredients, beating quickly until smooth. Spread over uncut pastry. Let icing become firm in the refrigerator before cutting into squares.