Ingredients

• 1 cup (226 grams) butter
• 3/4 cup (75 grams) Dutch processed cocoa powder
• 2 cups (400 grams) granulated sugar
• 1 teaspoon instant espresso powder
• 3 large eggs
• 1 tablespoon (15 ml) vanilla extract
• 1 teaspoon salt
• 1 1/2 cups (270 grams) semi-sweet or bittersweet chocolate, chopped
• 1 cup (120 grams) all-purpose flour
• Optional mix-ins: walnuts, pecans, toffee