Three Layer Brownies

1 Cup quick cooking rolled oats
1/2 Cup flour
1/2 Cup packed brown sugar
1/4 Teaspoon baking soda
6 Tablespoons margarine, melted
3/4 Cup sugar
1/4 Cup margarine, melted
1 Square (1 ounce) unsweetened chocolate, melted and cooled
1 egg
2/3 Cup flour
1/4 Teaspoon baking powder
1/4 Cup milk
1/2 Teaspoon vanilla
1/2 Cup chopped walnuts
1 Square (1 ounce) unsweetened chocolate
2 Tablespoons margarine
1 teaspoon vanilla
16 Walnut halves
Stir together oat, the 1/2 cup flour, brown sugar, soda, and 1/4 teaspoon salt. Stir in the 6 tablespoons margarine. Pat into 11 X 7 X 1 1/2 inch baking pan. Bake in 350 degree oven for 10 minutes; cool. Mix granulated sugar, the 1/4 Cup margarine and 1 Square melted chocolate. Add egg; beat well. Stir together the 2/3 Cup flour, baking powder, and 1/4 teaspoon salt. Add to chocolate mixture alternately with a mixture of milk and the 1/2 teaspoon vanilla. Stir in chopped nuts. Spread over baked layer. Bake in 350 degree over for 25 minutes or till done. Cool. To make frosting, melt 1 square chocolate and 2 tablespoons margarine over low heat; stir constantly. Remove from heat; stir in powdered sugar and the 1 teaspoon vanilla. blend in enough hot water (about 2 tablespoons) to make an almost pour able consistency. Frost brownies. Top with walnut halves. Cut into bars. Makes 16 brownies