We've covered cookies, cakes, puddings, and candies over these 12 days of sweet eating, but we'll end this series on a classic of unparalleled richness: chocolate and walnut brownies. This recipe has a sizable 16 tablespoons of butter, and it's worth it for the comforting boost of a warm a gooey mouthful. If you have trouble getting the brownies out of your baking pans, we have a technique that will help you attain a perfect brownie crust, crispy edges, and moist insides without any hassle. —The Editors