Banana Nut Brownies

1/2 cup butter, melted
1 cup sugar
3 tbsp cocoa
2 eggs, beaten slightly
1 tbsp milk
1 tsp vanilla
1/2 cup flour
1 tsp baking powder
1/4 tsp salt
1 cup mashed ripe bananas (2 1/2 to 3 medium)
1/2 cup chopped nuts

In a bowl, combine butter, sugar, and cocoa. Stir in eggs, milk, and vanilla. Blend in flour, baking powder and salt. Stir in bananas and nuts. Pour into a greased 9x9 inch square baking pan. Bake at 350F for 40 - 45 min.