1/2 cup all-purpose flour
1 cup quick-cooking rolled oats
1/2 cup packed brown sugar
1/4 teaspoon baking soda
1/2 cup butter, melted
1 egg
3/4 cup granulated sugar
2/3 cup all-purpose flour
1/4 cup milk
1/4 cup butter, melted
1 ounce unsweetened chocolate, melted and cooled
1 teaspoon vanilla
1/4 teaspoon baking powder
1/2 cup chopped walnuts
1 ounce unsweetened chocolate
2 tablespoons butter
1-1/2 cups sifted powdered sugar
1/2 teaspoon vanilla
Walnut halves (optional)
Recipe
1. For bottom layer, stir together oats, the 1/2 cup flour, the brown sugar, and baking soda. Stir in the 1/2 cup melted butter. Pat mixture into the bottom of an ungreased 11x7x1-1/2-inch baking pan. Bake in a 350 degree F. oven for 10 minutes.
2. Meanwhile, for middle layer, stir together egg, granulated sugar, the 2/3 cup flour, the milk, the 1/4 cup melted butter, 1 ounce melted chocolate, the 1 teaspoon vanilla, and the baking powder until smooth. Fold in chopped walnuts. Spread batter over baked layer in pan. Bake about 25 minutes more or until a wooden toothpick inserted in center comes out clean. Set on a wire rack while preparing top layer.
3. For top layer, in a medium saucepan heat and stir 1 ounce chocolate and the 2 tablespoons butter until melted. Stir in the powdered sugar and the 1/2 teaspoon vanilla. Stir in enough hot water (1 to 2 tablespoons) to make a mixture that is almost pourable. Spread over brownies. If desired, garnish with walnut halves. Cool completely on wire rack. Cut into bars. Makes 32 brownies.
Make-Ahead Tip: Prepare and bake brownies as directed. Frost and cool. Cover and store at room temperature for up to 1 day.