• Preheat oven to 350°F. Butter and line a 9x13-inch baking pan with buttered parchment.
• Whisk together the flour, cocoa powder and salt. Set aside.
• In a medium saucepan over medium-low heat, melt the butter to just simmering. Turn off the heat and add the chopped chocolate. Swirl the pan so the chocolate is submerged in the butter and let sit for 3 minutes. Gently whisk until smooth.
• In a bowl of a stand mixer, fitted with the whisk attachment, whip together the eggs, sugar and vanilla on medium-high speed until light and fluffy, about 5 minutes.
• Turn the speed to low and slowly add the melted chocolate mixture.
• Add the flour mixture to the chocolate mixture and stir just until combined.
• Pour into prepared pan and add toppings, if desired.
• Bake for about 35-40 minutes or until a tester comes out with moist crumbs. It can take much longer depending on your oven and ingredient temperature. If you like your brownies dense and gooey, bake them until the sides puff, but the center is still fudgy when tested. Note: All ovens are different, so the bake time may vary depending on the oven. An oven thermometer will help determine actual temperature.

Four Topping Variations

• Warm peanut butter in the microwave for a few seconds to make it spreadable. Swirl with a skewer, then add crushed Oreo pieces.
• Warm Nutella in the microwave for a few seconds to make spreadable. Swirl with a skewer, then add toasted hazelnuts.
• Add a mix of white, milk and dark chocolate chunks, stir half into the batter and top with the remaining.
• Last section left plain and simple.