The Best Millionaire’s Shortbread Ever

Millionaire’s shortbread, caramel shortbread, caramel slice, twix bars, whatever you wanna call ‘em. They’re all super tasty and so easy to make. This is one of my favorite treats whenever I visit the U.K., and each place does it differently. This recipe uses a standard 3:2:1 ratio for the crust, this ensures a nice crumbly shortbread biscuit. The point is to keep it as simple as possible without sacrificing any of the flavors.

The hardest part isn’t making them, it’s resisting the urge to eat more than a couple. They’re rich and buttery, and melt-in-your-mouth delicious. You ready? Let’s get started.

I’m using a 10-inch square pan so if you have a 9-inch, use the chart below to convert. The main recipe is for an 8-inch pan. If you don’t want to convert, you don’t have to. Warning, math ahead.

The trick for square pan conversions is to take the area of both pans and divide by the smaller number. For example, the area of my 10x10 inch pan is a 100 square inches. The original recipe call for an 8x8 inch square which gives you a 64 square inch area. 100 divided by 64 is 1.56, that means to convert from an 8 inch to a 10 inch pan, you need to multiply the ingredients by 1.5. The same rules apply for circular pans. Divide the larger area by the smaller one to find the multiple value for your conversion. To make things simple, this chart below will help you if you need to convert. Hooray for mathematical specificity! Here’s a little chart to help you convert.

So let’s get started!

Shortbread Crust:

100g or 1/2 cup Unsalted Butter, soft.

50g or 1/2 cup Sugar

150g or 1 cup + 2 tbsp All Purpose/Plain Flour

Caramel Filling:

200g or 2/3 cup Condensed Milk

150g or 2/3 cup Unsalted Butter

50g or 1/2 cup Sugar

50g or 3 tbsp Golden Syrup, can also use Honey or Maple Syrup

Chocolate Topping:

200g or 1 cup Chocolate Chips/Squares

Prep:

Preheat oven to 350F/175C. Line an 8-inch square pan with parchment paper and grease the sides with butter.

In a bowl, beat sugar and butter to form a smooth paste. Add flour and gently mix it all together. Use your hands to knead and mop up all the crumbs.

Flatten crust inside pan and try to level it as much as you can. Bake for 20-25 minutes or until your crust is a light golden brown around the edges. Let it cool in the pan.

While your crust is baking, start the caramel. Put all filling ingredients into a saucepan and place on medium-high heat, stirring gently. Watch it closely as you stir. If you see little brown slivers at the bottom of the pan, stir them in vigorously and turn the heat down to a low-medium. Simmer it gently until it reaches a deep, golden brown color.

It should take around 15 minutes.

When ready, pour the caramel over the cooled biscuit crust and spread evenly using an offset spatula or knife. Let this cool for at least an hour. You don’t want the caramel to be warm or it’ll ruin your chocolate. Don’t cool in the fridge or else you’ll end up with a hard mess. Melt chocolate using microwave or double boiler and pour over cooled caramel to finish off.

To serve, heat up a knife using hot water (make sure you dry it) or a blowtorch. This will ensure you get a nice clean cut. Cut into whatever size slices you want; I usually go for 1-inch squares.