Quick and Easy Brownies

INGREDIENTS
2 cups white sugar
1 cup butter
1/2 cup cocoa powder
1 teaspoon vanilla extract
4 eggs
1 1/2 cups all-purpose flour
1/2 teaspoon baking powder
1/2 teaspoon salt
1/2 cup walnut halves
DIRECTIONS
Melt the butter or margarine and mix all ingredients in the order given.
Bake at 350 degrees F for 20 to 30 minutes in a 9 x 13 inch greased pan.