Brown Butter Salted Caramel Slice - a toasty brown butter shortbread is topped with a chewy, silky brown butter caramel, and finished off with a smooth layer of chocolate. This is a slight twist on the classic bakery treat, and is sure to become a firm favourite.
Brown Butter Salted Caramel Slice
Hi! I hope you are staying safe! I’ve been hanging out at home, doing all of the puzzles and bopping around in my tiny NYC kitchen making all sorts of things - most recently, this brown butter salted caramel slice! There’s a brown butter shortbread base, a super chewy, silky brown butter caramel filling, and then a smooth chocolate topping to finish it all off, complete with some retro bakery style feathering if you feel like fancying it up a little bit (it’s easy and I’ll tell you all about it, I promise!).
I grew up eating caramel slice, or millionaire’s shortbread as I think it is called here in the states - it is a New Zealand bakery staple, and one of my favourite things. It varies from place to place in both the ratio of base to caramel, and also in the technique of the caramel. Some recipes will have you stir together a filling and then pop it in the oven to finish, but others will have you make a caramel on the stove top and pour it over the cooled shortbread base to set. I went for the stovetop method as I feel it is much easier to control and you know when it is done by using a thermometer to measure the temperature of the mixture.
How to make brown Butter salted Caramel Slice
I browned the butter for both the shortbread base and the caramel filling, which gives this a super toasty, extra delicious flavour. Browning butter is great because it adds so much flavour wise, without having to use any extra ingredients. The shortbread is super simple and I actually found it easiest to make it by hand rather than using a mixer, and just using a spatula instead to bring the base together. I creamed brown butter which I had chilled back down to be spreadable with some brown sugar, then added in some flour, vanilla and salt, to make a super smooth shortbread base which is insanely satisfying to pat into your baking pan. The shortbread base gets baked until it is nice and toasty, then once it is cool it is caramel time!
The secret ingredient for perfect caramel slice - Condensed Milk
The caramel filling is perfectly thick and chewy, and has a lovely silkiness to it, which is thanks to the Eagle Brand® Sweetened Condensed Milk that I used! I love all things condensed milk. It is perfect to have on hand for times like this when you just need a little caramel slice treat, and Eagle Brand is super simple - it’s only ingredients are milk and sugar! I started with the condensed milk and brown butter as a base, then added in some golden syrup for texture (set caramel benefits from an invert sugar), a little bit of brown sugar for colour and toastiness to help bring out the brown butter flavour, and a solid dose of salt.
I finished it off with a thin layer of dark chocolate, which I added a wee feather texture to by drizzling some white chocolate over the surface and feathering it using a cake tester. This is a totally optional step but it’s super easy and makes the caramel slice look a little fancy. You could also sprinkle a little flaky sea salt on the top of the chocolate topping instead of the feathering - you do you here!
Steps for Making Brown Butter Salted Caramel Slice
- Brown the butter. I'm going to get you to brown two just one large quantity here, which will be used in both the shortbread base and also in the caramel topping.
- Make the Shortbread Base - A toasty brown butter shortbread base is made and baked off until golden, then left to cool completely until it is ready for the caramel.
- Make the Caramel Layer - The Brown Butter Salted Caramel is a favourite of mine. It's such a simple twist on the classic that makes a huge difference in flavour. It all comes together in a pot - a candy thermometer is super helpful here, and then is poured over the shortbread base and left to set.
- Finish with Chocolate - Caramel slice usually has a thin layer of chocolate on the top, which gives it a beautiful finish. I like adding a little neutral oil to help it set super flat. This time I also went for the classic feathered top, which is a signature bakery finish!
- Cut up and serve - Use a super sharp knife to cut your salted caramel slice up. This stores for about two weeks in the fridge. Enjoy!
A few wee tips for Brown Butter Salted Caramel Slice:
- I am going to get you to brown all of the butter at once, so that you don’t have to do the process twice. You want to brown it and then place into a bowl or container and chill it down until it is a spreadable texture - either you can do this in the freezer, stirring often, or if you are making it ahead, just pop it in the fridge then bring out and let it come to a spreadable texture when you are ready to bake.
- You will notice that the quantity of butter needed is more than the quantity of brown butter that I call for in the recipe. When you cook brown butter, it loses volume from cooking out the water during the browning process, so the initial quantity of butter reflects the amount lost during the browning. I added just a touch more as a buffer so you’re not caught short!
- The brown butter for the caramel filling can be fridge solid and you can just plop it in - it will get melted so don’t worry about bringing that to room temp!
- I used golden syrup in the filling, but honey or corn syrup will work well too!
- The caramel needs to set for an hour and a half or two hours - I like to assemble it all and then set it overnight or for at least 3 hours just to make sure that it is all set.
- If you don’t want to brown the butter you can use the same amounts of unsalted butter.
- Adjust the salt content to what works for you!
- I like to use little bulldog clips to hold my parchment to my pan edges. If you get the unpainted ones they are fine to go in the oven.
For more Salted Caramel Recipes, check out:
- Salted Caramel Shortbread Bars
- Salted Caramel Chocolate Ganache Brioche Doughnuts
- Brown Butter Salted Caramel Chocolate Chunk Cookies
- Brown Butter Salted Caramel Tart
Thank you so much to Eagle Brand® Sweetened Condensed Milk for sponsoring this post. All opinions are my own.
Made this recipe and love it?
If you made this recipe then I would LOVE for you to leave me a review below to let me know how you liked it! Also, please make sure to tag me on Instagram if you make it!
A note on salt and oven temperature
It is important to note the type of salt that is called for in a recipe. I use Diamond Crystal salt throughout my recipes - if you use a different sort of kosher salt or regular table salt you will need to adjust accordingly as some salt is 'saltier' than others. Morton's salt is twice as salty, so you will need half the quantity. Same goes for a regular table salt. I am working to get gram measurements throughout my recipes for salt but still getting there.
All oven temperatures are conventional unless otherwise stated. If you are baking on fan / convection, you will need to adjust the temperature. An oven thermometer is a great investment to ensure that your oven is the correct temperature.
Using the double / triple function in the recipe card
You will notice that there is a '1X' '2X' '3X' button in my recipe card. This can be used for doubling or tripling a recipe. However, please note that this only doubles the ingredient quantities in the ingredients list and NOT in the method. If there are quantities or pan sizes in the method of the recipe (for example weigh out 150g brown butter), you will need to scale this number manually. It will also not change the baking time in the recipe so you will need to adjust this yourself too. It is always a good idea to read through a recipe fully before doubling it just to check this. If you would like to scale this recipe or convert for another pan size, use my calculator!
Tools and equipment
For a list of my go-to tools and equipment, I have a post you can refer to here.
Why is this recipe in grams?
I post my recipes in grams as it is the most accurate way to bake. Cups are not only inaccurate but they vary in volume worldwide. There is no way for me to provide one cup measure that works for everyone. However, posting in weight fixes this issue. If you would like the recipe in cups you are welcome to convert it yourself via google, but please do not ask me to do it for you as I am not comfortable providing a recipe using a method that I have not tested. Baking with a scale is easy, accurate, and also makes cleanup super simple. Here is the scale that I use if you would like a recommendation! Here's to accurate baking!Print
Toasty brown butter shortbread is topped with a chewy, silky brown butter caramel, and finished off with a smooth layer of chocolate.
- 380g unsalted butter, cold from the fridge is fine
Brown Butter Shortbread Base
- 170g brown butter, at room temperature, spreadable consistency (see notes)
- 85g dark brown or light brown sugar
- ½ tsp kosher salt
- ¾ tsp vanilla bean paste or vanilla extract
- 275g all-purpose flour
Brown Butter Salted Caramel Filling
- 1 14oz (400g) can Eagle Brand® Sweetened Condensed Milk
- 185g dark brown or light brown sugar
- 100g brown butter
- 50g golden syrup or corn syrup
- ¾ tsp kosher salt (drop to ½ tsp if you don’t like your caramel super salty)
- ½ tsp vanilla bean paste
- 180g dark chocolate
- 30g neutral flavoured oil
- Optional for feathering - 50g white chocolate melted with ½ tsp neutral flavoured oil
- Place the butter in a medium saucepan, and place over medium heat. Cook until the butter has melted, and then continue to cook, swirling the pan often, until the butter foams and turns golden brown and nutty - this should take 3-4 minutes.
- Transfer to a bowl, allow to cool slightly, then transfer the bowl to the freezer and chill the butter until solid. Remove from the freezer and bring to room temperature, stirring often, until soft and spreadable.
BROWN BUTTER SHORTBREAD BASE
- Preheat the oven to 325°f / 165°c. Grease an 8” (20cm) square pan and line with two pieces of parchment paper that extend over the sides of the pan to use as handles.
- In a medium bowl, cream together the spreadable brown butter and brown sugar using a spoon or spatula. Add the salt, vanilla, and flour, and bring together to form a soft, homogenous dough. Pat the dough into the bottom of the prepared pan, smoothing down with a flat bottomed measuring cup or offset spatula. Prick all over and chill for 10 minutes.
- Bake the base for 30 to 35 minutes, until set and evenly golden. Remove from the oven and allow to cool completely.
BROWN BUTTER SALTED CARAMEL FILLING
- Place the Eagle Brand® Sweetened Condensed Milk, brown sugar, brown butter and golden syrup in a medium sized heavy bottomed saucepan.
- Place over a medium heat and stir until melted together, then cook, stirring constantly with a whisk or rubber spatula (I like to use a whisk then switch to the rubber spatula), until the mixture registers 220°f / 105°c on a candy thermometer. Watch the bottom carefully to avoid the mixture catching, turning down the heat if needed.
- Once the caramel has reached the correct temperature, add the vanilla and salt, mix well to incorporate, and pour it over the cooled shortbread base and smooth off by shaking the pan and using an offset spatula if needed. Transfer to the fridge and allow to set for 1 to 1 ½ hours or until you can no longer feel heat in it.
- In a heat proof bowl set over a pot of simmering water, melt together the chocolate and the oil, stirring frequently, until smooth. Alternatively, melt together in the microwave in 30 second increments, stirring well after each.
- Pour over the set caramel filling, and tilt the pan to evenly coat. Bang the pan on the counter several times to smooth out the topping and eliminate any bubbles. If you would like to add the feathering, pipe horizontal stripes of the melted white chocolate across the surface, then feather using a skewer by dragging it up and down the surface of the chocolate, perpendicular to the lines that you piped.
- Chill in the fridge until completely set, at least an hour or up to overnight. Remove from the pan by using the parchment paper slings. cut into slices using a sharp knife, wiping between each. Store in an airtight container.
Keywords: Caramel Slice, Brown Butter, Salted Caramel, Millionaire's Shortbread