I finally mastered Mars Bar Squares with a quick no-bake method using only chocolate bars and Rice Krispies, and I’m sharing the clever trick that makes them come together perfectly every time.

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I know it sounds basic, but I keep coming back to these Mars Bar Squares. I cant explain why chopped Mars Bars and Rice Krispies belong in the same bar, only that they do, and every bite makes me wonder how something so messy could be so perfect.

The crackle of the crispy cereal against the gooey candy is like a tiny argument in your mouth you dont want to stop. I made them during a study break and ended up hiding the pan, no shame.

If you like treats that are wrong and right at the same time youll get this.

Ingredients

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Mars Bars: soft, chewy caramel and nougat, loaded with sugar and lots of quick energy.
Unsalted butter: adds rich fat, creaminess, helps bind, adds some vitamin A and mouthfeel.
Rice Krispies: light crunchy cereal, mostly carbs, little fibre or protein, dont add nutrients.
Milk chocolate: melts into glossy topping, sweet, contains sugar and dairy fat, comforting.
Vegetable oil or golden syrup: optional glossy finish, adds shine and slight sweetness, helps spreading.
Pinch of sea salt: brightens flavours, cuts through sweetness, use sparingly though, enhances chocolate.
Caramel: sticky, chewy, adds deep sweetness and gooey texture, keeps squares together.

Ingredient Quantities

8 to 10 Mars Bars (about 450g total), chopped

50g unsalted butter

6 cups Rice Krispies (Rice Bubbles), about 150–180g

200g milk chocolate, chopped (for topping)

1 tbsp vegetable oil or 1 tsp golden syrup, optional to make the topping glossy

Pinch of sea salt, optional

How to Make this

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1. Line a 20cm (8 inch) square tin with baking paper, leaving some overhang so you can lift the slice out later.

2. Chop 8 to 10 Mars Bars (about 450g) into pieces and put them in a heatproof bowl with 50g unsalted butter. Melt gently in the microwave in 20 second bursts, stirring between each, or melt in a saucepan over very low heat, stir till smooth. Dont let it boil or burn or it will go grainy.

3. Remove the melted Mars-bar mix from the heat and stir in 6 cups Rice Krispies (Rice Bubbles, about 150–180g) and a pinch of sea salt if using. Mix until every bit of cereal is coated and gooey.

4. Tip the mixture into the lined tin and press down firmly and evenly with the back of a spoon or a piece of baking paper so it packs together well. Wet your hands slightly or use a piece of parchment to press so it doesnt stick.

5. Chill the base in the fridge for 15 to 20 minutes so it firms up a bit while you make the chocolate topping.

6. Put 200g chopped milk chocolate in a bowl and add 1 tablespoon vegetable oil or 1 teaspoon golden syrup if you want a glossy finish. Melt in the microwave in short bursts, stirring often, or use a double boiler until smooth.

7. Pour the melted chocolate over the chilled Mars Bar base and spread evenly with a spatula. Sprinkle another tiny pinch of sea salt on top now if you like that sweet-salty contrast.

8. Return the tin to the fridge and let it set completely for at least 30 to 60 minutes until the topping is firm.

9. Lift the slice out using the paper overhang, cut into squares with a sharp knife warmed under hot water and dried between cuts for clean edges. Store in an airtight container in the fridge for up to 5 days or freeze for longer; let them sit a few minutes at room temp before eating if theyre rock hard.

Equipment Needed

1. 20cm (8 in) square baking tin, lined with baking paper with overhang
2. Heatproof mixing bowl for melting Mars Bars and chocolate
3. Microwave, or small saucepan plus extra heatproof bowl for a double boiler
4. Sharp knife and chopping board for cutting the bars
5. Measuring scales or measuring cups for the butter and Rice Krispies
6. Silicone spatula and wooden spoon for mixing and spreading
7. Spoon or piece of parchment to press the base evenly, wet hands also work, dont let it stick
8. Bowl of hot water and a clean tea towel to warm and dry the knife between cuts
9. Fridge and an airtight container for chilling and storage

FAQ

Q: How many Mars Bars do I need and does it matter if I use 8 or 10?

A: Use about 8 to 10 Mars Bars, roughly 450g total. 8 gives a firmer, less gooey result, 10 makes it softer and stickier. Either works fine, just depends how gooey you want it.

Q: What is the best way to melt the Mars Bars so they don't burn?

A: Chop them small, melt gently over low heat in a saucepan or use a double boiler. Microwave in 20 to 30 second bursts stirring between each burst also works. Add the 50g butter while melting to keep the mix smooth and don't walk away or it will scorch.

Q: Can I swap Rice Krispies or the chocolate topping for something else?

A: Yes. Use any puffed rice cereal (check weight so you get 6 cups). For the topping you can use other milk chocolate or a mix of milk and dark. If you swap bars for ones with nuts expect a different texture and extra crunch.

Q: How do I get a shiny, smooth chocolate topping?

A: Stir 1 tablespoon vegetable oil or 1 teaspoon golden syrup into the melted chocolate to make it glossy. Warm the chocolate gently, pour over cooled base and chill to set.

Q: How do I cut neat squares without the chocolate cracking?

A: Chill the tray until firm then use a sharp knife warmed under hot water and wiped dry between cuts. Lifting the slab out on parchment makes cutting easier. Cutting while still a bit cold gives cleaner edges.

Q: How should I store them and how long will they last?

A: Keep in an airtight container. At room temp they are best 2 to 4 days, in the fridge up to a week though chocolate gets firmer. You can freeze for up to a month, just thaw before serving.

Mars Bar Squares Recipe Substitutions and Variations

Mars Bars: swap with chopped Snickers, Twix or Cadbury Caramel (use about the same weight, 450g). Milky Way is the closest if you want the same soft caramel and nougat texture.
Unsalted butter: use salted butter in the same amount but skip any extra salt, or try coconut oil 1:1 for a dairy free version though it will lend a mild coconut taste.
Rice Krispies: any puffed rice cereal works 1:1, or for a different crunch use crushed cornflakes or crushed digestive biscuits in the same volume.
Milk chocolate (topping): replace with dark or white chocolate (200g) or use chocolate chips; add 1 tsp vegetable oil or 1/2 tsp golden syrup while melting to get a glossy finish.

Pro Tips

1) Don’t overdo the heat when melting stuff, you’ll scorch it fast. Melt in short bursts and stir between each blast, and if the mix looks grainy add a teaspoon of golden syrup or a little extra butter, it usually smooths it out.

2) Pack the cereal base really firmly so the slice holds together, but press with a sheet of baking paper or a wet spatula so your hands dont stick and you dont squash it unevenly. If it still seems soft after chilling, pop it in the freezer for 10 to 15 minutes before adding the chocolate.

3) For glossy, smooth chocolate work slowly and never let steam or water touch the bowl or chocolate or it will seize. If you want extra shine add a small amount of neutral oil or syrup once it’s just melted, dont overheat it.

4) For clean cuts warm the knife under hot tap water then dry it between slices, or chill the whole block until almost rock hard and saw quickly for neat edges. Store in an airtight container with layers separated by parchment so they dont stick.

Mars Bar Squares Recipe

Recipe by Tina Bueller

0.0 from 0 votes

I finally mastered Mars Bar Squares with a quick no-bake method using only chocolate bars and Rice Krispies, and I'm sharing the clever trick that makes them come together perfectly every time.

Servings

servings

Calories

345

kcal

Equipment: 1. 20cm (8 in) square baking tin, lined with baking paper with overhang
2. Heatproof mixing bowl for melting Mars Bars and chocolate
3. Microwave, or small saucepan plus extra heatproof bowl for a double boiler
4. Sharp knife and chopping board for cutting the bars
5. Measuring scales or measuring cups for the butter and Rice Krispies
6. Silicone spatula and wooden spoon for mixing and spreading
7. Spoon or piece of parchment to press the base evenly, wet hands also work, dont let it stick
8. Bowl of hot water and a clean tea towel to warm and dry the knife between cuts
9. Fridge and an airtight container for chilling and storage

Ingredients

8 to 10 Mars Bars (about 450g total), chopped
50g unsalted butter
6 cups Rice Krispies (Rice Bubbles), about 150–180g
200g milk chocolate, chopped (for topping)
1 tbsp vegetable oil or 1 tsp golden syrup, optional to make the topping glossy
Pinch of sea salt, optional

Directions

Line a 20cm (8 inch) square tin with baking paper, leaving some overhang so you can lift the slice out later.
Chop 8 to 10 Mars Bars (about 450g) into pieces and put them in a heatproof bowl with 50g unsalted butter. Melt gently in the microwave in 20 second bursts, stirring between each, or melt in a saucepan over very low heat, stir till smooth. Dont let it boil or burn or it will go grainy.
Remove the melted Mars-bar mix from the heat and stir in 6 cups Rice Krispies (Rice Bubbles, about 150–180g) and a pinch of sea salt if using. Mix until every bit of cereal is coated and gooey.
Tip the mixture into the lined tin and press down firmly and evenly with the back of a spoon or a piece of baking paper so it packs together well. Wet your hands slightly or use a piece of parchment to press so it doesnt stick.
Chill the base in the fridge for 15 to 20 minutes so it firms up a bit while you make the chocolate topping.
Put 200g chopped milk chocolate in a bowl and add 1 tablespoon vegetable oil or 1 teaspoon golden syrup if you want a glossy finish. Melt in the microwave in short bursts, stirring often, or use a double boiler until smooth.
Pour the melted chocolate over the chilled Mars Bar base and spread evenly with a spatula. Sprinkle another tiny pinch of sea salt on top now if you like that sweet-salty contrast.
Return the tin to the fridge and let it set completely for at least 30 to 60 minutes until the topping is firm.
Lift the slice out using the paper overhang, cut into squares with a sharp knife warmed under hot water and dried between cuts for clean edges. Store in an airtight container in the fridge for up to 5 days or freeze for longer; let them sit a few minutes at room temp before eating if theyre rock hard.

Notes

Below you’ll find my best estimate of this recipe’s nutrition facts. Treat the numbers as a guide rather than a rule—great food should nourish both body and spirit. Figures are approximate, and the website owner assumes no liability for any inaccuracies in this recipe.