Brownies with PB Frosting Ingredients Brownies 1/4 Cup Unsweetened Cocoa Powder 1 Cup All-Purpose Flour 1 Teaspoon Salt 1 Teaspoon Baking Powder 6 Ounces Semi-Sweet Chocolate 2 Sticks Unsalted Butter 1/2 Teaspoon Espresso Powder (optional) 4 Large Eggs 1 Cup Light Brown Sugar, tightly packed 1 Cup Sugar 1 Tablespoon Vanilla Extract PB Frosting