Ingredients:

• /2 cup butter
• 2/3 cup Dutch-processed cocoa powder
• 1 1/4 cups granulated sugar
• Three eggs
• 1/4 vegetable oil
• Two teaspoons pure vanilla extract
• 1 1/4 cups all-purpose flour
• 1/2 teaspoon baking powder
• 1/8 teaspoon baking 
• 1/2 teaspoon salt
• 1/2 cup semisweet chocolate chips (optional)
• One cup roasted, lightly salted peanuts (optional)

Direction:

• Heat oven to 350°F. Line a 8×8-inch baking pan with foil, or parchment paper. Leave a 2-inch flap on two sides, and spray with cooking spray.
• Melt butter in a medium saucepan-over medium-low heat. Remove from heat; using a whisk, beat in cocoa powder until smooth—cool 5 minutes.
• Add sugar; mix to combine. Then add eggs and vanilla-mix until incorporated. Next, add flour, baking powder, baking soda and salt. Stir until the mixture is moist. 
• Pour batter in the prepared pan.
• Bake for 45 to 50 minutes or until the center of brownies domes and begins to crack, and the toothpick inserted 2 inches from the edge comes out with a few moist crumbs. Allow brownie to cool in pan on a cooling rack, about 2 hours. Refrigerate uncovered 30 minutes.