Millionaire’s Shortbread

Step 1

Preheat oven to 350°F. Grease and line an 8x8-inch cake pan with parchment paper. 

Step 2 

In a medium bowl, beat butter,  granulated sugar, and dark brown sugar until light and fluffy. Add the egg yolk and vanilla extract. Beat on medium speed to incorporate egg yolk. Scrape the sides of the mixing bowl with a rubber spatula. Add half of the flour and salt and mix on low speed. Add the remaining flour and mix until just combined. Drop portions of the dough in the bottom of the pan; this will make it easier to spread out. Press the dough evenly into the bottom of the pan. A piece of parchment paper or the bottom of a ¼ dry measuring cup can also be used to help to even out the dough. Bake for approximately 20 minutes or until the edges are golden brown. Once baked, place baked crust on a cooling rack to cool. 

Step 3

Prepare the caramel filling. In a heavy, medium-sized saucepan, melt butter slowly on low heat. Once the butter is melted, add the salt and dark brown sugar. Mix well to combine and to ensure the mixture is lump free. Use a heat-proof silicon rubber spatula for the entire stirring process. When the mixture is well combined, add the sweetened condensed milk over low heat. Once the mixture is combined, attach the deep fat frying thermometer to the side of the pan. Over medium heat, bring to a boil, stirring constantly.  When the mixture starts boiling, stir the mixture continuously until a temperature of 220°F is reached. This should take approximately 25 minutes. The caramel will be a rich golden color and will start to pull away from the sides of the pan as you stir. Immediately remove from heat and add vanilla. Pour the caramel over the prepared crust. There is no need to let the caramel cool down at all. Cool at room temperature for several hours or for an hour at room temperature and cover and finish cooling in the refrigerator. If cooled in the refrigerator, let the pan come up to room temperature before topping with the chocolate ganache. 
 

Step 4

To prepare chocolate ganache, add chocolate chips to a glass or heat safe bowl over a small saucepan of simmering water. Melt chocolate chips and do not let any water get in the melted chocolate, as this will make the chocolate seize. In a microwave safe measuring cup, heat heavy whipping cream until hot. Pour the hot cream over top of the melted chocolate and stir with a small rubber spatula to combine. Let cool slightly before pouring over top of the caramel. 
 

Step 5

To finish decorating the bars, pour chocolate ganache on the caramel and use a knife or small spatula to spread out the ganache and make a swirl pattern. Sprinkle with the Maldon Sea salt if desired. Allow the ganache to set up; refrigerating for approximately 30 minutes works well. Once the chocolate has hardened, use a very sharp knife to cut 4x4 pieces. This will give a total of 16 pieces.