Buttery shortbread, soft caramel center, crackly chocolate topping. Divine! These may be the most sugar and fat-laden cookies I’ve ever made. That is, of course, why they are so good. I’d say, don’t make these more than once a year … but do make them.
This is a recipe being tested by Cook’s Illustrated. I am on their mailing list to test their recipes from time to time. This time, they admonished me thusly: “… we respectfully ask that you do not post the working recipe online or in any other media until the final recipe has been published in the magazine. And if you do share the final recipe in a public forum, please remember to give us credit.” But given the fact that, unlike their major competitors, most of their web content is behind a stingy subscription fee, I decided to pass the secret on to my readership. I am a long-time subscriber to Cook’s Illustrated magazine as well as their confusing array of websites. I enjoy their America’s Test Kitchen television show. I love their well tested recipes and their thoughtful equipment reviews. I am far from a naysayer but I find it difficult to recommend their web content when people are required to pay an annual fee to access it.
But, kvetching aside – this is a very, very tasty treat. Give it a try.
- 2½ cups (12 ½ ounces) all-purpose flour
- ½ cup (3 ½ ounces) granulated sugar
- ¾ teaspoon salt
- 16 tablespoons unsalted butter, melted
- 1 (14-ounce) can sweetened condensed milk
- 1 cup (7 ounces) brown sugar
- ½ cup heavy cream
- ½ cup corn syrup
- 8 tablespoons unsalted butter
- ½ teaspoon salt
- 6 ounces bittersweet chocolate, chopped
- 2 ounces bittersweet chocolate, grated
- For the Crust: Adjust oven rack to lower-middle position and heat oven to 350 degrees. Line bottom and sides of 13- by 9-inch baking pan with aluminum foil. Combine flour, sugar, and salt in medium bowl. Add melted butter and stir with rubber spatula until flour is evenly moistened. Crumble dough evenly over bottom of prepared pan. Using your fingertips and palm of your hand, press and smooth dough into even thickness. Using fork, pierce dough at 1-inch intervals. Bake until light golden brown and firm to touch, 25 to 30 minutes. Transfer pan to wire rack. Using sturdy metal spatula, press on entire surface of warm crust to compress (compressing crust while warm will make cutting finished bars easier). Cool crust to just warm, at least 20 minutes.
- For the Filling: Stir all ingredients together in large, heavy-bottomed saucepan. Cook over medium heat, stirring frequently, until mixture registers between 236 and 239 degrees (temperature will fluctuate), 16 to 20 minutes. Pour over crust, and spread to even thickness (mixture will be very hot). Cool completely, about 90 minutes.
- For the Chocolate: Microwave 6 ounces chopped chocolate at 50 percent power, stirring every 15 seconds, until fully melted but not much warmer than body temperature, 1 to 2 minutes. Add 2 ounces grated chocolate, and stir until melted, returning to microwave for no more than 5 seconds at a time to complete melting if necessary. Spread chocolate evenly over surface of filling. Refrigerate shortbread until chocolate is just set, about 10 minutes.
- Using foil, remove shortbread from pan and transfer to cutting board; discard foil. Using serrated knife and gentle sawing motion, cut shortbread in half crosswise to create two 6 ½- by 9-inch rectangles. Cut each rectangle in half to make four 3 ½ - by 9-inch strips. Cut each strip crosswise into equal 10 pieces. (Shortbread can be stored at room temperature, between layers of parchment, for up to one week.)