1 c. butter, softened, divided
1 1/2 c. sugar
2 eggs
2/3 c. mashed banana
2 tsp. vanilla extract
2 c. sifted flour
1 tsp. baking powder
1/2 tsp. baking soda
1 tsp. salt
1 tsp. cinnamon
1/2 c. milk
1 1/2 c. chopped nuts
2 c. powdered sugar

Cream 1/2 cup butter and sugar in bowl until light and fluffy. Add eggs; beat well. Stir in banana and 1 teaspoon vanilla. Sift next 5 ingredients together. Add alternately with milk to creamed mixture, mixing well after each addition. Stir in 1/2 cup walnuts.

Spread batter in a greased and floured 10 x 15 inch jelly roll pan. Bake at 350 degrees for 20-25 minutes. Combine powdered sugar, 3 tablespoons butter, 2 tablespoons hot water and 1 teaspoon vanilla in small bowl until creamy. Frost warm bars. Sprinkle remaining nuts and cut into bars.