Millionaire Shortbread Recipe

I’m sharing How To Make Millionaire Shortbread with a buttery shortbread crust, a gooey caramel core and a glossy chocolate ganache top, plus the one simple trick I use so the caramel sets cleanly.

When I first bit into a millionaire shortbread I was surprised by how the crisp, buttery shortbread and a gooey middle play against a glossy chocolate top. I couldnt stop wondering what small tweak flipped it from good to unforgettable.

In my version i lean hard on really good unsalted butter for the base and a can of sweetened condensed milk to get that perfectly sticky middle, then I let the chocolate sing. If you like trickier sweet treats this is for you, and yes I even tag it How To Make Millionaire Shortbread because people always ask.

Ingredients

• Unsalted butter for shortbread: rich, makes tender crumb, high in fat and calories
• Caster sugar: sweet, helps structure shortbread, simple carbs, not much nutrition
• Plain all purpose flour: provides bulk and structure, mostly carbohydrates and some protein
• Sweetened condensed milk: creamy, makes sticky caramel, very sweet, lots of sugar and calories
• Soft light brown sugar: adds deeper caramel notes and moisture, contains molasses, more flavour
• Golden syrup: concentrated sweetener, helps caramelise, sticky, mostly sugar with little else
• Dark chocolate: bittersweet finish, provides antioxidants, it’s still high in fat and sugar though
• Flaky sea salt optional: small sprinkle balances sweetness, adds crunch and flavour contrast

Ingredient Quantities

• 225g unsalted butter, softened (for shortbread)
• 100g caster sugar
• 300g plain all purpose flour
• pinch of salt
• 1 can 397g sweetened condensed milk
• 100g unsalted butter (for caramel)
• 100g soft light brown sugar
• 2 tbsp golden syrup
• 200g good quality dark chocolate or milk chocolate if you prefer
• 1 tbsp vegetable oil or 25g unsalted butter (to gloss the chocolate)
• flaky sea salt optional, for sprinkling

How to Make this

1. Preheat oven to 180C/350F/gas 4 and line a 20x30cm (8x12in) tin with baking paper, leaving an overhang so you can lift the bars out later.

2. Make the shortbread: beat 225g softened unsalted butter with 100g caster sugar until pale and a bit fluffy, stir in 300g plain flour and a pinch of salt until it just comes together into a dough. Press evenly and firmly into the lined tin, prick the surface with a fork and bake for 20 to 25 minutes until pale golden. Let it cool in the tin until completely cool.

3. Make the caramel: in a heavy based saucepan combine 1 can (397g) sweetened condensed milk, 100g unsalted butter (for the caramel), 100g soft light brown sugar and 2 tbsp golden syrup. Heat gently, stirring all the time until the sugar melts, then simmer very gently for about 8 to 12 minutes until thick, deep golden and it coats the back of a spoon. Keep it moving or it will stick and burn. Warning: it gets very hot.

4. Pour the caramel over the cooled shortbread and spread it evenly with a spatula. Tap the tin on the counter to remove any air bubbles. Chill in the fridge for at least 1 hour so the caramel firms up.

5. Prepare the chocolate topping: chop 200g good quality dark chocolate (or milk if you prefer) and melt it gently with 1 tbsp vegetable oil or 25g unsalted butter in a heatproof bowl set over barely simmering water, or in the microwave in 20 second bursts, stirring between each burst until glossy and smooth. Dont overheat or it will seize.

6. Pour the glossy chocolate over the set caramel, spread to a smooth even layer, then sprinkle flaky sea salt if you like that salty-sweet hit.

7. Chill until the chocolate is completely set, at least 1 to 2 hours or overnight for the cleanest slices.

8. Remove from tin using the paper overhang, slice into squares or bars with a sharp knife warmed under hot water and wiped dry between cuts for clean edges. Store in the fridge if your kitchen is warm, or in an airtight tin for up to 5 days.

Equipment Needed

1. 20x30cm (8x12in) baking tin lined with baking paper leaving an overhang so you can lift the bars out later
2. Kitchen scales for weighing everything in grams
3. Large mixing bowl
4. Hand mixer or a sturdy wooden spoon for beating the butter and sugar
5. Heavy based saucepan for the caramel
6. Silicone spatula for spreading the caramel and chocolate
7. Heatproof bowl or microwave safe bowl for melting the chocolate
8. Fork to prick the shortbread and a sharp knife to slice the bars (warm under hot water between cuts)
9. Measuring spoons and a tablespoon
10. Cooling rack and a tea towel to dry the knife between slices

FAQ

Millionaire Shortbread Recipe Substitutions and Variations

• Unsalted butter (shortbread): swap with salted butter, use same weight but cut the added pinch of salt, or use block vegan/baking margarine 1:1 for a dairy free option, or solid coconut oil 1:1 (gives a slightly crisper, faint coconut taste).
• Caster sugar: use regular granulated sugar (same weight) after pulsing briefly in a blender or food processor to make it finer, or use fine golden caster sugar for a touch of caramel flavor, or light brown sugar for a softer, chewier shortbread but expect a darker color.
• Sweetened condensed milk (caramel): replace with canned dulce de leche (equal weight) for a deeper caramel note, use canned sweetened condensed coconut milk for dairy free swaps, or a jarred caramel sauce (about 350 to 400g) but check thickness and sweetness before spreading.
• Golden syrup: use light corn syrup 1:1 as a neutral substitute, use honey 1:1 (flavor will change and caramel may be slightly softer), or maple syrup 1:1 for a stronger, maple-y twist.

Pro Tips

1) Dont overwork the shortbread dough, and press it firmly and evenly so you dont end up with thin edges and a thick middle. Use the base of a measuring cup or a straight spatula for an even surface, that way the caramel spreads smoothly and you get tidy bars.

2) For the caramel use a heavy pan and keep the heat very low, stir constantly and scrape the sides and bottom with a heatproof spatula. If you have a candy thermometer aim for the mixture to reach the soft ball stage about 112 to 115C if you want a reliably set but still gooey caramel, but the spoon test works fine too.

3) Melt the chocolate very slowly and keep all water away, even one tiny droplet will make it seize. Add the oil or butter at the end to smooth and gloss it, and if you need the chocolate to set faster pop the tin in the fridge for a short time but dont leave it too long or you might get condensation bloom.

4) For the cleanest slices warm a sharp knife under hot water and wipe it dry between cuts, or score the chocolate lightly first then finish the cut. Store the bars at room temp if your kitchen is cool so the caramel stays soft, otherwise fridge them and let them sit a few minutes before serving so they soften up.