If you’re looking for an easy homemade recipe that delivers maximum chocolatey goodness with minimal fuss, these Mars Bar Brownies are about to become your new favourite bake. They’re gooey, rich, nostalgic, and—best of all—completely irresistible. This is the kind of kid‑friendly recipe that gets the whole family hovering around the kitchen waiting for the brownies to cool… if they can wait that long.
This recipe is inspired by the iconic Mars Bar Brownies from Jane’s Patisserie, a blog I’ve loved and baked from for years. Her version is legendary, but after making it several times, I started tweaking it to suit my own preferences—slightly different ratios, a few optional add‑ins, and a method that fits the rhythm of my own kitchen. The result is this delicious, deeply fudgy brownie that I’m thrilled to share with you today.
If you need a quick dessert that still feels special, this one checks every box.
Table of Contents
A Short History of the Mars Bar
The Mars Bar has a surprisingly rich and storied past for such a simple, beloved chocolate treat. It was first created in 1932 in Slough, England, by Forrest Mars Sr., who modelled it after his father Frank Mars’ already‑popular Milky Way bar, adjusting the recipe to better suit European tastes . Early production was modest—Forrest Mars worked with only a handful of employees and even sourced chocolate from Cadbury due to limited resources at the time (source : Snack History).
The classic bar we know today—milk chocolate wrapped around soft nougat and caramel—quickly became a staple across the UK and later much of the world. Over the decades, the Mars Bar has seen several recipe tweaks, logo redesigns, and even a few quirky historical moments. For example, three million Mars Bars were shipped to British forces during the Falklands War in 1982, cementing its place as a cultural icon as well as a comfort food .
Despite these changes, the essence of the Mars Bar has remained the same since its debut: a sweet, satisfying combination of chocolate, caramel, and nougat that continues to inspire bakers—myself included—to create indulgent treats like these Mars Bar Brownies.
Why You’ll Love These Mars Bar Brownies
Ultra fudgy texture thanks to whisked eggs and brown sugar
Chunks of frozen Mars Bar that melt into pockets of caramel and nougat
Simple ingredients you probably already have
Perfect for kids, bake sales, parties, or a weekend treat
Customizable—add chocolate chips, drizzle melted chocolate, or top with extra Mars Bar pieces
Ingredients
200 g chocolate chips
200 g unsalted butter
3 large eggs (or 4 medium)
275 g light brown sugar
100 g plain flour
25 g cocoa powder
120 g Mars Bar, chopped and frozen (about 2 bars)
150 g milk chocolate chips (optional)
Mars Bar Brownie Recipe
Mars Bar Brownies
Ingredients
Equipment
Method
- Heat your oven to 180°C or 355℉. Line a 9×9" baking tin with parchment paper or aluminum foil.
- In the microwave or over a pan of simmering water, melt the 200g of chocolate chips and butter together until smooth. Set aside to cool slightly.
- Beat the eggs and brown sugar on high for about 5 minutes. Pour the cooled chocolate mixture into the whisked eggs and fold gently to keep the air in.
- Sift in the flour and cocoa powder. Fold again until just combined.
- Fold in the frozen Mars Bar chunks and chocolate chips (if using). Freezing the Mars Bar helps keep the caramel from melting too quickly.
- Pour the batter into your prepared tin and bake for 25–30+ minutes, depending on how fudgy you like them. The centre should wobble slightly but not be liquid. I like 35 minutes and I cover it with aluminum foil for the last 10 minutes.
- Let the brownies cool completely to room temp before slicing. This helps them set into that perfect fudgy texture. Refrigerate once room temp.
Notes
Optional Decoration
If you want to take things up a notch (and honestly, why not?), drizzle melted chocolate over the cooled brownies and top each square with a piece of Mars Bar. Pop the tray into the fridge to set before slicing.
Tips for Perfect Brownies Every Time
- Don’t skip whisking the ingredients for 5 minutes—this is what gives you that classic brownie top.
- Use frozen Mars Bar pieces so they hold their shape better during baking.
- Let them be wobbly out of the oven for maximum fudginess.
- Let them cool fully before cutting—trust me, it’s worth the wait.
Final Thoughts
“These are the best brownies I have ever had!” – my 8 year old son
These Mars Bar Brownies are everything a brownie should be: rich, gooey, chocolate‑packed, and dangerously moreish. They’re simple enough for a weekday bake yet indulgent enough for a celebration. Whether you’re making them with your kids, for your kids, or just for yourself, this easy homemade recipe is one you’ll come back to again and again.
If you try them, let me know how they turned out—I love hearing from fellow chocolate lovers.
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