Prepare for a delightful journey into a world where sticky caramel, rich chocolate, and chewy nougat perfectly blend with crispy cereal. Our no-bake Mars Bar Squares are the answer to your sweetest cravings, offering an unbelievably easy and utterly addictive dessert experience. Imagine a treat that’s wonderfully gooey, satisfyingly crunchy, and crowned with a luscious layer of milk chocolate – all without ever turning on your oven. These squares, often affectionately known as Mars Bar Slice in Australia, are a true revelation for anyone seeking a quick, delicious, and utterly irresistible confection.

These aren’t just any ordinary no-bake bars; they are an elevated take on the classic Rice Krispie treat, transforming a simple concept into a rich, decadent experience. While traditional Rice Krispie treats rely on marshmallows, butter, and chocolate, our Mars Bar Squares harness the magic of whole Mars bars. The distinctive nougat core of Mars bars beautifully mimics the gooiness of marshmallows, while their signature milk chocolate and creamy caramel layers infuse every bite with an unparalleled depth of flavor. To make them even more indulgent, we crown them with an extra layer of melted milk chocolate, though this delightful addition is entirely optional.

Mars Bar Squares hold a special place as a fantastic summertime delight, effortlessly prepared without the need for an oven. Their sturdy, no-mess nature makes them perfect for picnics, road trips, or any outdoor gathering. However, their appeal extends far beyond the warmer months; they’re also an ingenious way to utilize surplus Halloween candy or a go-to recipe whenever a profound chocolate craving strikes. Interestingly, while known as “Mars Bar Squares” in many parts of the world, in Australia, they are commonly referred to as a “Mars bar slice” or even “Mars bar Rice Bubble slice,” a nod to Rice Krispies being known as Rice Bubbles Down Under.

Crafting the Perfect Mars Bar Rice Krispie Treat: Achieve Optimal Gooeyness

The secret to truly outstanding Mars Bar Squares lies in achieving the perfect balance between the rich chocolate-caramel mixture and the crispy cereal. We want bars that are wonderfully gooey but still firm enough to hold their shape and slice cleanly. After extensive testing, we’ve fine-tuned the ingredient ratios to deliver that ideal texture every single time. This carefully calibrated recipe ensures your bars will be soft and chewy without being overly crumbly or too stiff.

For bars that strike this delightful balance, you’ll need:

• 1/2 cup unsalted butter (112 grams)
• 4 standard Mars bars (each typically 53 grams), chopped
• 3 cups Rice Krispies / Rice Bubbles
• 1 cup milk chocolate chips, or 200 g chopped milk chocolate for the luxurious topping

Should your preference lean towards an even gooier consistency – truly bordering on marshmallow-like chewiness – you can slightly reduce the cereal amount. Simply use 2 1/2 cups of Rice Krispies instead of 3 cups. This small adjustment will enhance the melted Mars bar mixture’s dominance, resulting in a softer, more indulgent treat.

The journey to these delectable squares begins in a large, heavy-bottomed saucepan. Start by gently melting the unsalted butter over very low heat. It’s crucial to use low heat to prevent scorching the butter. Once the butter is mostly melted, introduce the chopped Mars bars. Cutting them into smaller pieces will help them melt more evenly and quickly. Continuously stir the mixture with a spatula or wooden spoon as the chocolate and caramel begin to soften and meld into the butter. Patience is key here; maintaining low heat is paramount to prevent the delicate caramel and chocolate from burning, which can impart an unpleasant, bitter taste. The goal is a smooth, glossy, and uniform chocolate-caramel sauce.

Expert Tip: If you notice the butter and melted chocolate bars starting to separate – appearing oily or grainy – don’t panic! This can sometimes happen if the heat is slightly too high or if the mixture is agitated too much. Simply remove the pan from the heat immediately and whisk vigorously for a minute or two. The emulsification will usually come back together, yielding a perfectly smooth and cohesive mixture once more.

Once the Mars bar mixture is completely melted and beautifully smooth, remove the saucepan from the heat. This is the moment to gently fold in the Rice Krispies. Ensure every crispy piece is thoroughly coated with the warm, gooey chocolate-caramel mixture. Work quickly but carefully to prevent the cereal from becoming soggy. The goal is to distribute the cereal evenly so that each square offers a harmonious blend of textures.

Next, transfer this enticing mixture into a lightly greased 8×8 inch (20×20 cm) square baking pan. Using a spatula or the back of a spoon, gently but firmly press the mixture down into an even layer. Avoid compacting it too much, as this can make the bars overly dense. A light, even press is sufficient to ensure they hold together. While a 9×9 inch pan can be used, be aware that your Mars Bar Squares will be noticeably thinner, altering the bite and overall experience.

The final touch is a generous layer of creamy, melted milk chocolate spread over the top. This adds another dimension of chocolatey goodness and creates a beautiful, glossy finish. After applying the topping, the bars need time to set. I always recommend allowing them to firm up at room temperature. Placing chocolate in the refrigerator to speed up hardening can sometimes lead to discoloration, resulting in those peculiar white “bloom” flecks on the surface. Room temperature setting ensures a smooth, even, and professional-looking chocolate topping that snaps beautifully when sliced.

Expert Tips & Tricks for Perfect No-Bake Mars Bar Squares

• Mars Bar Alternatives: If traditional Mars bars are hard to find in your region, don’t fret! Milky Way bars (the European version, not the American one which is more like a 3 Musketeers) make an excellent substitute, offering a similar nougat and caramel profile. You could also experiment with other caramel-filled chocolate bars for a unique twist.
• Chocolate Topping Variety: While milk chocolate provides a classic, sweet finish, feel free to customize your topping. Semi-sweet chocolate will add a slightly richer, less sweet counterpoint, while dark chocolate can offer a sophisticated, intense cocoa flavor that balances the sweetness of the Mars bars perfectly.
• Melting Chocolate Like a Pro: When melting your chocolate for the topping, especially in the microwave, proceed with caution. Always use medium power and heat in short 45-second bursts. After each interval, remove the bowl and stir thoroughly, even if it doesn’t look fully melted. Chocolate retains its shape even when melted, so stirring is essential to distribute the heat and prevent burning. Continue until smooth and glossy. Alternatively, a double boiler offers a gentler, more controlled melting method.
• Preventing Chocolate Cracks: A common issue with chocolate-topped bars is cracking when you slice them. To avoid this, once your chocolate topping is about 80% hardened (it will still feel slightly pliable but no longer liquid), gently score the top surface with a thin, sharp knife where you intend to cut your squares. This creates guide lines and pre-weakens the chocolate, allowing for clean, crisp slices once fully set.
• Scaling the Recipe: This recipe is incredibly versatile and easily doubled. If you’re feeding a crowd or simply want more of these delightful treats, double all the ingredients and use a larger 9×13 inch baking pan. Adjust the setting time slightly if needed for the larger batch.
• Storage Recommendations: For optimal freshness and texture, store your Mars Bar Squares in an airtight container at room temperature for up to 4 days. While tempting, I generally advise against refrigerating or freezing them. The cold can cause the chocolate topping to discolor or “bloom,” and the bars themselves can become excessively hard and crunchy, losing their signature gooeyness. If freezing is your only option, thaw them slowly in the refrigerator overnight, then allow them to come to room temperature on the counter before enjoying for the best results.
• Serving Suggestions: These squares are fantastic on their own, perhaps with a glass of cold milk or a cup of coffee. They also make a wonderful addition to dessert platters, bake sales, or as a thoughtful homemade gift.

If you’ve fallen in love with the simplicity and deliciousness of no-bake treats, be sure to explore more of our easy recipes. They’re perfect for satisfying your sweet tooth without the fuss of baking:

• Peanut Butter Rice Krispie Treats
• No-Bake Rocky Road Bars
• Hedgehog Slice

Rating: 5 out of 5 stars (based on 2 votes)

Mars Bar Squares

By: Fiona Dowling

What do you get when you melt together chocolate bars and mix them with Rice Krispies? These delicious, no-bake Mars Bar Squares, also known as Mars Bar Slice. They’re gooey, crunchy, topped with milk chocolate, and absolutely addictive.

Prep: 10 mins

Resting: 2 hrs

Total: 2 hrs 10 mins

Servings: 16 squares

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Equipment

• 8×8 inch (20×20 cm) pan

Ingredients

• 1/2 cup unsalted butter (112 grams)
• 4 Mars bars (53 grams each), chopped
• 3 cups Rice Krispies (about 90 grams) , aka Rice Bubbles
• 1 cup milk chocolate chips (about 200 grams), or chopped milk chocolate

Instructions

1. Lightly grease an 8×8 inch (20×20 cm) square baking pan.
2. Add the butter to a large saucepan and gently melt the butter over low heat.
3. Add the chopped Mars bars to the butter and gently stir the mixture as the Mars bars begin to melt.
4. Continuously stir the mixture until smooth. If the butter and chocolate bars start to separate, remove from the heat and whisk until smooth. Stir constantly to avoid burning.
5. Once melted, turn off the burner and stir in the Rice Krispies/Rice Bubbles. Feel free to use 2 1/2 cups (instead of 3 cups) for gooier bars.
6. Spoon the batter into the prepared pan, and gently press it down. You can lightly grease a spatula or spray your hands with non-stick cooking spray if you find the mixture keeps sticking.
7. Add the chocolate chips/chopped chocolate to a heatproof bowl. Microwave on medium power for 45-second intervals, stirring between each. Once the chocolate is almost melted, stir until smooth. Alternatively, melt in a double boiler over low heat. Ensure that the water underneath does not touch the bottom of the bowl with the chocolate.
8. Spread the mixture over the bars and let sit for 2 hours at room temperature, or until the chocolate is hardened before slicing. When the chocolate topping looks about 80% hardened, use a thin knife to trace along the top where you plan to slice the bars. This makes slicing easier because the chocolate topping won’t crack.

Notes

1. Rice Krispies: For gooier bars, use 2 1/2 cups Rice Krispies/Rice Bubbles.
2. Storage: Store in an airtight container at room temperature for up to 4 days. I do not recommend storing in the fridge or freezing the bars because the chocolate topping can discolor, and they can end up getting too hard and crunchy. If you choose to freeze them, thaw in the fridge overnight then let them sit on the counter at room temperature before enjoying.
3. Nutrition: Nutrition info is based on 1 square, with the pan sliced into 16 pieces. It is an estimate only.

Nutrition

Calories: 183kcal, Carbohydrates: 22g, Protein: 1g, Fat: 11g, Saturated Fat: 5g, Cholesterol: 17mg, Sodium: 36mg, Potassium: 7mg, Fiber: 1g, Sugar: 8g, Vitamin A: 552IU, Vitamin C: 3mg, Calcium: 15mg, Iron: 2mg