Also known affectionately as Millionaire’s Shortbread, these decadent three-layer dessert bars are the absolute pinnacle of holiday treat trays, bake sales, and cozy weekend baking. With a buttery, melt-in-your-mouth Scottish shortbread base, a thick center layer of gooey, golden salted caramel, and a snappy crown of bittersweet dark chocolate finished with flaky sea salt, every single bite is pure confectionery bliss.
Making real caramel at home often strikes fear into bakers, with worries of crystallized sugar and scorching. However, this foolproof recipe uses sweetened condensed milk, brown sugar, butter, and golden syrup to create a rich, chewy caramel that comes together smoothly on the stovetop with zero candy thermometers required.
The Architecture of the Perfect Shortbread Bar
Each of the three layers provides an essential sensory role in building the ultimate bar:
- The Crisp Butter Shortbread Base: Made with just butter, sugar, and flour, this layer is pressed firmly into the pan and pre-baked until pale golden. It provides the firm, crumbly structural foundation that prevents the bar from collapsing when picked up.
- The Chewy Caramel Heart: Simmering butter, brown sugar, and condensed milk creates a silky caramel that sets firmly enough to slice cleanly, yet remains delightfully soft, chewy, and gooey at room temperature.
- The Dark Chocolate Cap: Bittersweet dark chocolate (60% to 70% cacao) balances the rich sweetness of the caramel, while a whisper of coconut oil in the melted chocolate prevents the top layer from cracking into jagged shards when cut.
Chewy Salted Caramel Shortbread Bars
Ingredients
14 itemsLayer 1: The Shortbread Base
Layer 2: The Gooey Salted Caramel
Layer 3: The Dark Chocolate Top
Instructions
11 steps-
01
Prep Pan and Oven: Preheat your oven to 350°F (175°C). Line an 8×8-inch square metal baking pan with parchment paper, leaving generous overhang on opposite sides to create a “sling” for lifting the chilled bars later.
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02
Make the Shortbread: In a mixing bowl, combine melted butter, granulated sugar, vanilla extract, and salt. Stir in the flour until a soft, crumbly dough forms. Press the dough firmly and evenly into the bottom of the prepared baking pan using the flat bottom of a drinking glass. Prick all over with a fork to prevent bubbling.
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03
Bake Shortbread: Bake for 18 to 20 minutes until the edges are lightly golden and the center feels set. Remove from oven and let cool slightly on a wire rack while you prepare the caramel.
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04
Cook the Caramel: In a medium heavy-bottomed saucepan, combine the 1/2 cup butter, brown sugar, sweetened condensed milk, and maple syrup over medium-low heat. Stir continuously with a heat-proof rubber spatula until the butter and sugar melt together completely.
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05
Simmer to Thick Perfection: Increase heat slightly to medium. Bring the mixture to a gentle boil, stirring constantly and scraping the bottom and sides of the pan so the milk sugars don’t scorch. Simmer vigorously for 6 to 8 minutes. The caramel will darken to a rich golden amber color and thicken substantially into a fudge-like consistency. Remove from heat and stir in vanilla extract and sea salt.
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06
Pour and Set: Immediately pour the warm caramel over the baked shortbread crust, spreading it into a smooth, even layer with an offset spatula. Let rest at room temperature for 15 minutes, then transfer to the refrigerator for 30 minutes to firm up.
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07
Melt Chocolate: In a microwave-safe bowl, combine chocolate chips and coconut oil. Microwave in 30-second increments at 50% power, stirring well between bursts, until completely melted, smooth, and glossy.
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08
Top and Chill: Pour melted chocolate over the chilled caramel layer, gently tilting the pan so the chocolate flows evenly to all four corners. Let sit at room temperature for 10 minutes, then sprinkle flaky sea salt over the chocolate. Refrigerate for at least 1 1/2 to 2 hours until the chocolate and caramel are fully set.
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09
Slice into Squares: Run a thin knife along the unlined edges of the pan. Using the parchment paper sling, lift the entire block out of the pan onto a cutting board. Using a large chef’s knife warmed under hot water and wiped dry, slice cleanly into 16 squares, wiping the blade clean between cuts.
Chef’s Notes
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10
Stir Without Stopping: When simmering the caramel, never walk away from the stove. Milk sugars in condensed milk can burn quickly if not constantly stirred.
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11
Hot Knife Slicing: Running your knife under hot tap water and drying it with a towel before slicing warms the blade, allowing it to glide through the chocolate layer without shattering it.
Frequently Asked Questions
Can I double this recipe for a 9×13 pan?
Yes! Double all ingredients exactly and bake in a standard 9×13-inch baking pan, adding 3 to 5 minutes to the shortbread baking time.
How long do these bars last?
Stored in an airtight container between sheets of parchment paper, these bars keep fresh in the refrigerator for up to 2 weeks, or frozen for up to 3 months.
Serving Suggestion
Serve slightly chilled or at cool room temperature with a steaming cup of Earl Grey tea or black roast coffee.
