Millionaire's Shortbread Bars
Millionaire’s shortbread bars are the rags-to-riches story of classic shortbread — proof that a little extra effort can turn ordinary shortbread into the most eye-catching option on your cookie platter.
FOR THE SHORTBREAD, WHISK:
FOR THE CARAMEL, HEAT:
FOR THE TOPPING, HEAT:
Pressed for time? Opt for a purchased caramel spread to make these bars a little quicker.
Preheat oven to 350°. Line a 9-inch baking pan with parchment paper.
For the shortbread, whisk together flour, ground peanuts, 2 Tbsp. cornstarch, and salt in a bowl; set aside.
Cream 1½ sticks butter and granulated sugar with a mixer on medium speed. Mix in flour mixture until combined but sandy.
Press shortbread into prepared pan; bake until golden and set, 30–35 minutes. Transfer pan to a rack to cool.
For the caramel layer, heat brown sugar, 4 Tbsp. butter, corn syrup, and espresso powder in a medium saucepan over medium until boiling, 3 minutes.
Whisk together ⅔ cup cream, egg yolks, and 3 Tbsp. cornstarch; stir into caramel. Cook, stirring, over medium heat until thickened, 5 minutes.
Pour caramel over cooled shortbread; chill or let stand until caramel is firm. Cut shortbread into 18 rectangles.
For the topping, heat ½ cup cream and shortening until boiling; pour over chocolate in a bowl and let stand 5 minutes. Stir chocolate until smooth.
Dip top of each cookie into chocolate, sprinkle on chopped peanuts, and let stand until chocolate is set.