Dark Chocolate Whole Wheat Brownies

Bahan-bahan (12 porsi)

• 6 ounces dark or semisweet chocolate chips
• 10 tablespoons butter
• 1 1/4 cups sugar
• 2 teaspoons vanilla extract
• 3 large eggs
• 2/3 cup , plus 2 tablespoons whole wheat flour ((see note below for all-purpose flour))
• 1/2 teaspoon baking powder
• 1/2 teaspoon kosher salt
• 1/3 cup dark or bittersweet chocolate chips