Guinness Brownies

Bahan-bahan (16 porsi)

• 8 ounces semisweet chocolate (cut into pieces)
• 5 tablespoons unsalted butter (at room temperature)
• 1/2 cup whole wheat pastry flour
• 1/4 cup all-purpose flour
• 1/2 cup unsweetened cocoa powder (plus 1 tablespoon )
• 1/4 teaspoon kosher salt
• 3/4 cup granulated sugar
• 3 large eggs (at room temperature)
• 1 teaspoon pure vanilla extract
• 3/4 cup Irish stout beer (plus 2 tablespoons, such as Guinness, at room temperature with any foam skimmed off)
• 3/4 cup semisweet chocolate chips
• 1/2 cup unsalted butter ((1 stick) at room temperature)
• 2 1/2 cups powdered sugar
• 1 teaspoon pure vanilla extract
• 2 -3 tablespoons Irish stout (such as Guinness)