A few weeks ago, a good friend of mine who lives in San Francisco sent me an email with the subject line "Millionaire's shortbread." She explained that she had recently attended a green living fair where the owner of Clairesquares was serving her millionaire's shortbread -- shortbread with caramel and chocolate on top. Even though I had never tasted millionaire's shortbread before, the name rang a bell with me, as it's one of the recipes included in Baked: New Frontiers in Baking. Because I am not a big fan of shortbread, I had never been particularly interested in trying the recipe. But my friend was quite effusive about it and explained that the millionaire's shortbread she had tasted was a much yummier version of a Twix candy bar (the cookbook uses the same analogy: "Think of this bar as the rich man's Twix"). I love Twix and its combination of crunchy cookie and gooey caramel, so I decided to give the recipe a try.
The shortbread layer of this bar is made from sugar, butter, flour, and an egg yolk. You mix together all of the ingredients except for a half cup of the flour (most of the flour goes in at the beginning) in a mixer. Then you turn out the dough and form it into a square, sprinkle the reserved half cup of flour on top, and fold the dough over repeatedly until the flour is absorbed. Working the flour in by hand in this fashion is a messy process, and I'm not quite sure why the recipe doesn't just have you add in all of the flour together at the beginning. You press the dough into the bottom of a 9-inch by 13-inch pan and bake it until golden brown.
The recipe provides two methods for making the caramel layer, a stovetop method and a microwave method. Since we don't own a microwave, the choice was easy! For the stovetop method, you simply heat two cans of condensed milk in a double boiler until it's thick and caramel colored. According to the directions, this should take about an hour to an hour and a half. I made this recipe twice, and both times it took about two hours. You pour the caramel over the cooled crust and refrigerate the pan for a few hours until the caramel is firm. Then you finish off the bars with a layer chocolate glaze (chocolate melted together with a little corn syrup and butter). You put the bars back in the fridge until the glaze sets, and then you can cut and serve the bars.
I was surprised how much I liked these; they are, in fact, way better than a Twix. I liked these bars the straight out of the fridge, the same way I prefer my Twix. Chilling the bars helps keep the caramel firm and also makes the shortbread seem a little crunchier, which is a fantastic contrast to the other two layers. The shortbread is buttery and tender, the caramel is rich and decadent, and the chocolate is chocolate (enough said there). These simple yet luxurious bars hit all of the right notes, and definitely live up to their highfalutin name.
Recipe: "Millionaire's Shortbread" from Baked: New Frontiers in Baking, by Matt Lewis and Renato Poliafito.