Once upon a time traveling in England, I had an amazing wedge of shortbread covered in caramel and chocolate. The setting could not have been more perfect: a tea shop in the Lake District on a rainy, blustery day. I drank a ton of tea in England (obviously), but that shortbread stayed with me. I didn’t realize until years later watching the Great British Baking Show that the treat had a name, and its name was millionaire’s shortbread.
I’ve made millionaire’s shortbread once before, but this recipe, which I found at The Pioneer Woman and adapted just slightly, is an improvement on the one I’ve made before. While the base is a little crumbly for me, the caramel layer is excellent, and I decided to go with a milk chocolate ganache on the top for a sweeter, less bitter treat. I know, do you really need something sweeter with shortbread and caramel? Just ask the folks at Twix, I suppose.
Ingredients
For the base
- 2 3/4 cups flour
- 3/4 cup sugar
- 1/4 cup cornstarch
- 1/4 teaspoon sea salt
- 1 cup plus 2 tablespoons unsalted butter, melted
- 1 teaspoon vanilla extract
For the caramel
- 14-ounce can sweetened condensed milk
- 1 cup light brown sugar
- 1/2 cup unsalted butter, cubed
- 1/2 cup light corn syrup
- 1/3 cup heavy cream
- 1/2 teaspoon sea salt
- 1 teaspoon vanilla extract
For the milk chocolate ganache
- 1 3/4 cups milk chocolate chips
- 100 milliliters (just above the 1/3 cup line, sorry Americans but there’s no easy conversion here) heavy cream
Preparation
Preheat oven to 350 degrees. Line a 9 x 13 baking tin with foil, extending the foil over the sides. In a large bowl, combine flour, sugar, cornstarch, sea salt, melted butter, and vanilla extract and stir until the dough comes together and becomes crumbly – be careful not to overwork it. Press dough into the pan and bake for 25-30 minutes, until edges are golden brown. Remove from oven and allow to rest while you make your caramel.
To make the caramel, combine sweetened condensed milk, brown sugar, butter, corn syrup, heavy cream, and sea salt in a medium pan and stir well. Cook over medium heat until the mixture darkens, begins to pull away from the pan, and reaches 235 degrees; I use a candy thermometer clipped to my pan and I stir constantly once the mixture begins to bubble to avoid scorching. Once the mixture reaches 235 degrees, remove from the heat and stir in the vanilla extract. Immediately pour over shortbread and allow to set at room temperature until cool.
Once the caramel is cool, make your ganache; there are different schools of thought on how best to do this, and I combined two different methods because I don’t think I got the cream warm enough on my first try. Place chocolate chips in a heatproof bowl. Place heavy cream in a small saucepan over low to medium heat and heat until it’s just about to boil – you’ll see small bubbles on the surface. Remove from heat and pour over chocolate chips; allow to sit for a few minutes to melt the chocolate, then stir vigorously until smooth. If necessary (and it was for me), place the mixture in the microwave and heat in short bursts of about 15 seconds, stirring well between each, until completely smooth. Pour over caramel layer and spread evenly with a spatula; allow to set before cutting. Slice into 2-inch x 1-inch pieces; store in airtight containers in a single layer (otherwise the layers get squished) at room temperature for 3-4 days. Makes 56.
So, millionaire’s shortbread. A shortbread cookie base with a layer of caramel and a layer of chocolate. Rich, right? You really have no idea just how rich until you try this recipe, which I found at 
amy bakes in the 'burgh 