These Mars Bar Brownies are gooey chocolate and caramel heaven. They are made up of a super fudgey and luxurious chocolate brownie, swirls of rich caramel sauce, and they're absolutely packed with Mars bar pieces! If you've not had a Mars bar before, it's a chocolate bar featuring nougat and caramel covered in chocolate. They belong in these rich chocolate brownies and this is guaranteed to be a treat you'll make again and again!
Ingredient Tips & Equipment Information
- Make sure your eggs are at room temperature before you start baking. The butter can be cold for this recipe, as you are going to melt it anyway. It will just take slightly longer to melt.
- I used unsalted butter for this recipe.
- I used light brown soft sugar for the brownies, which I do recommend using as it makes them extra fudgey, but you can also use caster sugar.
- If you need a caramel sauce recipe, try my Homemade Caramel Sauce.
- For all of the answers to more questions about brownies, check out my Chocolate Brownies guide!
- Although I provide cup measurements, I highly recommend weighing your ingredients out using digital kitchen scales*. It is the most accurate way to measure ingredients and will ensure the best results. Digital scales are very low cost and can be purchased for around £12 ($16.50) .
- For teaspoon (tsp) and tablespoon (tbsp) measurements, please use measuring spoons* and not the type of spoons you eat with. Again this will ensure accuracy and provide the best results.
For the full recipe with measurements, head to the recipe card at the end of this post.
How to make Mars Bar Brownies
Start by chopping up the Mars bars and putting them in the freezer. To make the brownies, melt the butter and dark chocolate together on a low heat, then leave to cool for 10 minutes. Whisk the eggs and brown sugar together using an electric mixer for 5 minutes. Add the vanilla extract and mix in.
Slowly pour the melted chocolate and butter mixture into the egg mixture, whisking as you pour. Then mix in the flour. Gently stir in the chopped up Mars bars, then pour the whole mixture into the baking tin.
Add the caramel sauce on top in blobs, then use a knife to swirl it into the brownie batter. Bake for 15 minutes, then add more chopped up mars bars on top and bake for a further 5-10 minutes, or until a cocktail stick poked into the centre comes out with moist crumbs on it, but is not wet. Leave to cool completely before slicing, you can put them in the fridge for a firmer brownie.
Can these brownies be baked in different size tins?
Yes! All you need to do is adjust the baking time. Bake for 20 minutes if using a 9" x 12" traybake tin, 30 minutes if using a 9" square tin, or 40 minutes if using a 8" square tin. Test they are done by poking in the centre with a cocktail stick. It should come out with moist crumb on it, but not be wet. I wouldn't recommend using anything smaller than an 8" square tin though.
What type of chocolate is best for brownies?
It’s hard to give an exact answer, because it depends on personal preference, but most dark chocolates will work well. I would always say to use a dark chocolate that you like to eat. One of the main ingredients of this recipe is melted dark chocolate, so it contributes massively to the flavour of the brownies. If you prefer a very dark chocolate that’s less sweet then use a higher cocoa bar, for example 70% cocoa and higher. If you prefer a milder dark chocolate, then a cocoa content around 40-50% will suit you better. One chocolate I would avoid using is cheap cooking or baking chocolate. You can get good quality baking chocolates (for example Lindt make one, and I have made amazing brownies with it) but any cheaper lower quality brands can taste very ‘fake’. For more tips on making brownies, check out my Chocolate Brownie making guide!
How should the brownies be stored and can they be frozen?
They should be stored in an airtight container, or covered on a plate, in a cool place for up to 3 days. You can also freeze the brownies. Once they are fully cool, wrap them well in cling film or place them in a freezer bag, and freeze for up to 3 months.
What caramel sauce is best to use?
My favourite caramel sauce to use is my Homemade Caramel Sauce, it's rich, smooth and absolutely divine! You can also easily add salt to it to make it into a salted caramel sauce. If you don't want to make your own, it's quite easy nowadays to find a good quality ready made caramel (or salted caramel) sauce in the shops or online. I have used Tesco's Finest, Bonn Maman and Carnation Caramel in the past with great results.
How do you know when the brownies are baked?
The best way to check is with the toothpick test, poke one into the middle of the brownies. It should come out with a few moist crumbs on it, but not be wet. It's better to underbake brownies rather than overbake them, especially for fudgey brownies, and you can always put them in the fridge to firm up.
Can the brownies be made gluten free?
For gluten free you can replace the plain flour with a gluten free plain flour blend. Unfortunately Mars bars are not gluten free, the closest alternative is Snickers which are gluten free. Please do check the labels of everything you use if you are serving this recipe to anyone with an allergy or intolerance.
Can the brownies be made dairy free?
To make the brownies dairy free, use a dairy free butter alternative. I recommend Flora Plant, or the Stork Baking Block. Or you can replace the butter for 200ml vegetable oil (or another mild tasting oil like sunflower or canola oil). You will also need to make sure the dark chocolate you use in the brownie batter is dairy free, as well as the caramel sauce. Unfortunately, Mars bars are not dairy free. There are some dairy free caramel nougat bars available on the market, Buttermilk and Twilight are brands I know of, that you could swap them for. Please do check the labels of everything you use if you are serving this recipe to anyone with an allergy or intolerance.
More tips for making the Mars Bar Brownies:
- Use a regular butter knife to make the swirls, glide it around slowly until you're happy
- Make sure to line your tin with greaseproof baking paper so the brownies come out easily
- I used 8 x 39.4g Mars bars for the brownies, then another 3 to decorate the top
Troubleshooting
If you have any questions about this recipe, or if something went wrong and you need help, please use the comment form below and I will get back to you. You can also get in touch with me on my Twitter, Instagram or Facebook. I'd love to hear from you!
Recommended equipment & ingredients*
- Mixing bowls
- Traybake tin
- Cooling rack
- Kitchen scales
- Electric hand mixer
- Piping bags
- Measuring spoons
- Dark chocolate
- Salted Caramel Sauce
- Mars bars
*I earn a small amount of money if you buy the products after clicking on the links. You will not be charged anything extra for this. Thank you for supporting The Baking Explorer!
More brownie recipes...
Mars Bar Brownies
Ingredients
For the brownies
- 350 g Dark chocolate
- 250 g Butter unsalted
- 250 g Light brown sugar
- 3 Eggs large
- 1 tsp Vanilla extract
- 120 g Plain flour
- 315 g Mars bars chopped up and frozen
- 125 g Caramel sauce good quality shop bought or homemade
For decoration
- 120 g Mars bars chopped up
Instructions
- Chop up the Mars bar for the brownies, and freeze for at least 1 hour
- Pre-heat your oven to 160C Fan/180C/350F/Gas Mark 4 and grease and line a 12" x 9" tin (see notes if you have a different sized tin)
- Melt the dark chocolate and butter together in a pan on a low heat. When fully melted, stir together and remove from the heat. Let it cool for 10 minutes
- In a mixing bowl use an electric mixer to whisk together the eggs, light brown sugar and vanilla extract for 5 minutes until thicker and paler in colour
- Add the chocolate mixture to the egg mixture, whisking constantly as you pour it in
- Add the plain flour and whisk in gently with a hand whisk until you can't see any more flour
- Gently mix the chopped and frozen Mars bar chunks into the brownie batter
- Pour the batter into your lined tin. Add spoonfuls of the caramel sauce all over the brownie batter, then use a butter knife to swirl it into the batter
- Bake for 15 minutes, remove from the oven and press the Mars bar pieces in all over for decoration
- Put back in the oven for 5-10 minutes, or until a cocktail stick poked into the centre comes out with moist crumbs on it, but is not wet
- Let the brownies cool completely in the tin before removing and slicing up
- Store in an airtight container in a cool place and eat within 3 days
Notes
- Make sure your eggs are at room temperature before you start baking. The butter can be cold for this recipe, as you are going to melt it anyway. It will just take slightly longer to melt.
- I used unsalted butter for this recipe.
- I used light brown soft sugar for the brownies, which I do recommend using as it makes them extra fudgey, but you can also use caster sugar.
- If you need a caramel sauce recipe, try my Homemade Caramel Sauce.
- For all of the answers to more questions about brownies, check out my Chocolate Brownies guide!
- Although I provide cup measurements, I highly recommend weighing your ingredients out using digital kitchen scales*. It is the most accurate way to measure ingredients and will ensure the best results. Digital scales are very low cost and can be purchased for around £12 ($16.50) .
- For teaspoon (tsp) and tablespoon (tbsp) measurements, please use measuring spoons* and not the type of spoons you eat with. Again this will ensure accuracy and provide the best results.
Josh
This is a 10/10 recipe. Went down very well
thebakingexplorer
Thank you so much for the lovely feedback Josh!