Brownies (Quick and Easy)

Ingredients

• 2 cups white sugar
• 1 cup butter
• 1/2 cup cocoa powder
• 1 teaspoon vanilla extract
• 4 eggs
• 1 cup all-purpose flour
• 1/2 teaspoon baking powder
• 1/2 teaspoon salt
• 1/2 cup walnut halves