Jamie Oliver Mars Bar Cake Recipe

This Jamie Oliver Mars Bar Cake Recipe is an absolute knockout if you’re after something sweet, nostalgic, and effortlessly fun. It’s got that gorgeous gooey-chewy texture from the Mars Bars, a crispy Rice Krispies crunch, and a smooth, rich chocolate topping that’s just irresistible. I made this on a whim for a midweek treat and couldn’t believe how simple it was to pull together—and how quickly it disappeared! (inspired by Jamie Oliver)

Ingredients Needed

Base

• 115 g (½ cup) Butter or Margarine
• 230 g (about 4–5 bars) Mars Bars, roughly chopped
• 130 g (4½ cups) Rice Krispies

Topping

• 250 g (1 cup) Milk Chocolate

How To Make Jamie Oliver Mars Bar Cake

Prep the Tin:
Start by lining an 11×7-inch baking sheet with greaseproof paper. This makes lifting and slicing the cake super easy once it’s set.

Melt the Mars Bars and Butter:
In a large heatproof bowl, combine the chopped Mars Bars and butter or margarine. Place the bowl over a bain-marie (or use a microwave in short bursts), stirring regularly until the mixture becomes glossy and mostly smooth. It won’t look perfect because of the nougat, but don’t worry—that adds to the gooey charm.

Mix in the Rice Krispies:
Once your mixture is melted, take it off the heat and gently fold in the Rice Krispies. Stir thoroughly to coat every last bit with that sticky, delicious Mars Bar blend.

Press into the Tin:
Tip the mixture into your lined tray and press it down firmly using the back of a spoon or spatula. Make sure it’s evenly packed into the corners—it’ll help everything hold together once chilled.

Make the Chocolate Topping:
Melt the milk chocolate in a clean bowl over a bain-marie or in the microwave. Pour the melted chocolate over the Rice Krispies base, spreading it gently with a spatula until smooth and even.

Let It Set:
Pop the tray in the fridge for at least 3 hours—or overnight if you can wait. Once it’s firm, slice into squares or bars and enjoy!

Why I Love This Recipe

I made this one rainy afternoon with my niece and nephew, and it was such a hit. They loved helping with the mixing (and licking the spoons), and I loved not having to switch on the oven. It’s so nostalgic—like those school bake sale treats, but better. Plus, it’s perfect for parties or a cheeky tea-time indulgence.

Recipe Tips

• Cut Mars Bars Evenly: This helps them melt more consistently with the butter.
• Melt Slowly: Always use low heat or short microwave bursts to avoid burning.
• Pack the Base Firmly: Press the mixture tightly into the tin to prevent it from crumbling later.
• Smooth Topping: Let the melted chocolate cool slightly before pouring—it’ll spread more evenly.
• Make It Your Own: Add nuts, sea salt, or even caramel drizzle for extra flair.

How To Store This Jamie Oliver Mars Bar Cake Recipe

At Room Temperature

Best avoided unless your kitchen is cool—it can get a bit melty!

In the Fridge

Store in an airtight container for up to 1 week. The texture stays perfect and the chocolate topping remains firm.

In the Freezer

Wrap portions tightly in cling film, then foil, and freeze for up to 3 months. Defrost overnight in the fridge before serving.

Nutrition Facts (per serving)

• Calories: 228
• Carbs: 31.3g
• Protein: 3.2g
• Fat: 10.1g
• Sugar: ~20g
• Fibre: 1.6g
• Sodium: ~0mg

Let’s Answer a Few Questions!

Can I use dark chocolate instead of milk for the topping?
Totally! Dark chocolate adds a more intense flavor and cuts the sweetness a bit.

Do I need to use real Mars Bars?
Ideally yes, but you can sub in any nougat-caramel-style bar if that’s what you have.

Can I make this gluten-free?
Yes—just use gluten-free puffed rice cereal and check the labels on your chocolate and Mars Bars.

What’s the best way to slice it neatly?
Use a sharp knife dipped in hot water. Wipe between cuts for clean squares.

Try More Recipes:

• Jamie Oliver Vegan Chocolate Brownies
• Jamie Oliver Chocolate Fridge Cake
• Jamie Oliver No Bake Chocolate Oat Bars