Millionaire shortbread features a buttery shortbread crust, a gooey caramel filling, and a rich chocolate ganache topping. These bars are incredibly rich, hence the name!
The combination of textures and flavors in these millionaire shortbread bars makes eating just one slice impossible.
To make the bars, a buttery shortbread crust is topped with a soft caramel filling before a layer of homemade chocolate ganache is added. And because I can’t resist salty-sweet treats, I sprinkled flaky sea salt over the chocolate ganache.
One bite of this incredibly rich dessert will show you why they’re called “millionaire” bars!
Although this is a layered dessert, each component is easy to make and the bars can be prepped days before you plan on serving them. A 9×13-inch pan of bars stretches to make 24 servings easily, making this a great party dessert that’s not your standard brownies or bars!
For being a three-layer dessert, these chocolate-caramel shortbread bars have a surprisingly short and straightforward ingredients list. As such, it’s important that you use exactly what the recipe calls for.
Here’s a look at the key ingredients in this recipe:
- Egg Yolks: I prefer adding egg yolks to my shortbread (like my thumbprint cookies) because it keeps it soft. Be sure to use egg yolks that are at room temperature. If you forget to set your eggs out ahead of time, place them in a bowl of warm water for 10 minutes.
- Sweetened Condensed Milk: Make sure to use sweetened condensed milk and not evaporated milk for this recipe. Sweetened condensed milk is sweeter and much thicker, which is what you want to make the caramel.
- Chocolate: I highly recommend using semi-sweet chocolate bars for the topping. Chocolate chips have stabilizers added to them so they don’t melt as well. Two bars of semi-sweet chocolate, like Bakers or Ghirardelli, work best.
- Heavy Whipping Cream: The cream is heated together with the chocolate to create the ganache topping. You must use a cream that’s at least 36% fat. Regular milk or half and half won’t work.
- Sea Salt: These millionaire bars are very sweet, so I suggest sprinkling a little bit of flakey sea salt on top. It helps balance out the sweetness of the bars and adds even more flavor.
How to Make Millionaire Shortbread
You’ll make the caramel shortbread bars in this order: shortbread crust, caramel filling, then chocolate ganache topping. The bars will need to cool in between layers, so don’t make this recipe if you’re in a time crunch!
- Preheat the oven and prepare your pan: Preheat the oven to 350°F (180°C). Line a 9×13-inch baking dish with parchment paper. I like to leave a decent amount of overhang so the bars are easier to remove from the pan later.
- Make the shortbread: Beat the butter and sugar until well combined, but not fluffy. (We’re making shortbread, not a cake!). Add the egg yolks and salt, followed by the flour. Stop to scrape down the sides of the bowl as needed. It’s best to only mix the shortbread crust until it starts to come together, but is still crumbly. I do the same thing with my lemon bar recipe, it makes it much easier to press into the pan!
- Bake the shortbread crust: Press the shortbread dough into the prepared baking pan and bake until the edges are golden and the top is set.
- Cool completely: The shortbread crust needs to cool completely before you add the caramel layer. If needed, you can place it in the refrigerator on a wire rack to speed up the cooling process.
- Make the caramel filling: Combine the sweetened condensed milk, brown sugar, butter, and corn syrup in a large saucepan and place over medium heat. The caramel mixture needs to be brought to a boil, then whisked constantly for about 8 to 13 minutes while it cooks.
- Test the caramel to see if it’s done: The caramel is done once it turns a caramel color and starts to thicken. To test it, fill a glass with cold water and drop a small spoonful of caramel into it. If you can form a soft ball with the mixture, then it’s ready. If you can’t, keep on cooking the caramel.
- Stir in the vanilla and salt: Once it’s done and removed from the heat, stir in the vanilla extract and salt.
- Pour the caramel over the shortbread crust: The caramel will be pretty thick, so I suggest using an angled spatula or a spoon to spread it out into one oven layer.
- Chill the caramel layer: Place the pan into the fridge for about 1 hour, or until the caramel is mostly set.
- Make the chocolate ganache topping: Combine the chopped chocolate and heavy whipping cream in a large bowl. Microwave until melted. I like to do this in 20-second increments, stirring regularly.
- Spread the ganache over the caramel layer: Then, sprinkle with optional sea salt.
- Chill the bars: They’ll need to sit in the fridge for at least 1 to 2 more hours before they’re firm enough to slice and serve.
Storage & Freezing Instructions
These millionaire shortbread bars can be stored on your counter or in the fridge for up to four days. If you live in a warm environment, you may want to keep the bars in the fridge as the ganache topping will soften otherwise.
The bars can also be frozen for up to three months. When ready to eat, simply thaw them overnight in the fridge.
- Make sure to wear an oven mitt while you’re cooking the caramel to avoid any hot splatters.
- The caramel filling requires constant stirring, so set a timer and don’t walk away while you’re stirring the pot. You’ll known it’s finished when the mixture has thickened, turned caramel in color (almost like butterscotch pudding), and begins to pull away from the sides of the pan.
- For best results, use regular chocolate bars and full-fat heavy whipping cream to make the ganache topping. If you use a lower fat alternative like half and half or milk, the ganache won’t set up properly.
More Cookie Bars You’ll Love!
- Chocolate Chip Cookie Bars
- Magic Cookie Bars
- Classic Blondies
- Peanut Butter Chocolate Chip Bars
For the shortbread crust:
- 1 cup unsalted butter softened (230 grams)
- ½ cup granulated sugar (100 grams)
- 2 large egg yolks at room temperature
- ¼ teaspoon salt
- 2 cups all-purpose flour spooned & leveled (250 grams)
For the caramel:
- 2 (14-ounce) cans sweetened condensed milk (NOT evaporated milk)
- 1 ¼ cups packed light brown sugar (250 grams)
- ¾ cup unsalted butter sliced (170 grams; 1.5 sticks)
- ¼ cup light corn syrup (70 grams)
- 1 teaspoon pure vanilla extract
- ¼ teaspoon salt
For the ganache:
- 8 ounces semi-sweet chocolate bars finely chopped (226 grams)
- ⅓ cup heavy whipping cream (80 ml)
- Sea salt for sprinkling on top optional but recommended
- To make the shortbread crust: Preheat the oven to 350°F (180°C). Line a 9x13-inch baking pan with parchment paper, making sure to leave some overhang for easy removal, and set aside.
- In the bowl of a stand mixer fitted with the paddle attachment or in a large mixing bowl using a handheld mixer, beat the butter and sugar until well combined, about 2 minutes.
- Mix in the egg yolks and salt until fully combined, stopping to scrape down the sides of the bowl as needed.
- Add the flour and continue mixing on low speed until the mixture starts to come together, but is still crumbly.
- Scoop the crumbly mixture into the prepared baking pan and press it down into one even layer.
- Bake for 23 to 28 minutes, or until the top is set and the edges are lightly golden brown. Remove from the oven and set aside to cool completely on a wire rack. If needed, you can place it in the refrigerator on a wire rack to speed up the cooling process.
- To make the caramel: In a large saucepan, combine the sweetened condensed milk, brown sugar, sliced butter, and corn syrup.
- Place over medium heat, whisking frequently until it comes to a boil. Continue cooking for 8 to 13 minutes, whisking constantly, until the mixture thickens, starts to pull away from the sides of the pan, and turns a caramel color. I recommend wearing an oven mitt while you are whisking the mixture to avoid any hot splatters. You can test the mixture to make sure it’s done by filling a glass with cold water and dropping a small spoonful of caramel into it. If you can form a soft ball with the mixture, then it’s ready. If you can't, keep on cooking the caramel.
- Remove from the heat and stir in the vanilla extract and salt until fully combined.
- Pour the caramel over the cooled shortbread crust and spread it around into one even layer. Refrigerate for 1 hour or until the caramel is mostly set.
- To make the ganache: Combine the chopped chocolate and heavy whipping cream in a large heat-proof bowl. Microwave in 20-second increments, stirring well after each increment, until the chocolate is completely melted and smooth.
- Remove the pan from the refrigerator, pour the chocolate ganache on top, and spread around into one even layer. Sprinkle the top with sea salt.
- Return to the refrigerator and chill for 1 to 2 hours or until the chocolate is set and firm.
- Lift the bars out of the pan using the overhang from the parchment paper, slice into pieces, and serve.
Shortbread crust adapted from my homemade lemon bars