Marbled Chocolate & Hazelnut Caramel Slice

This Marbled Chocolate & Hazelnut Caramel Slice is a luxurious twist on the classic Chocolate Caramel Slice.

It features three indulgent layers: a chocolate biscuit base, a rich caramel filling infused with toasted hazelnuts, and a beautiful, marbled chocolate topping.

Perfect for dinner parties or special occasions, this slice is easy to transport and sure to impress with its striking layers and elegant marbled chocolate finish.

Ingredients & Substitutions

Biscuit Base

Flour

I use plain (all-purpose) flour for this recipe, but you could self-raising flour and omit the baking powder. While I haven’t tried gluten-free substitutions, gluten-free flour or oat flour could work, although they might result in a crumbly texture.

Baking Powder

Baking powder adds a little lift to prevent the base from being too dense.

Brown Sugar

Brown sugar gives the biscuit base a caramel-like flavour and a moister consistency than white sugar.

Butter

Butter is essential for binding the dry ingredients and adding a richness that would not be achieved with oil. I recommend salted butter for a more flavourful result, but unsalted butter works too.

Almond Meal

Almond meal contributes both flavour and texture. If you have an almond allergy, hazelnut meal or desiccated coconut could be good alternatives.

Dark Chocolate

Melted dark chocolate brings the ingredients together to create a rich, decadent dough for the chocolate biscuit base.

Caramel Filling

Condensed Milk

Sweetened condensed milk is irreplaceable in this recipe as it’s the foundation of the caramel. You could use light condensed milk instead of full fat, but the dessert will remain indulgently sweet.

Golden Syrup

Golden syrup provides depth of flavour and ensures the caramel tastes rich and authentic. If you can’t find golden syrup, light molasses may be a substitute, but I haven’t tried it myself.

Butter

Butter is essential for the taste and texture of the caramel. I use salted butter because it enhances the flavour, but unsalted works too.

Caster Sugar

Caster sugar provides sweetness and ensures the caramel has the correct consistency.

Hazelnuts

Hazelnuts add a delicious crunch and flavour. You can buy them pre-toasted or toast them yourself in the oven for 5 minutes at 160°C (fan forced). If you’re not a fan of hazelnuts, macadamia nuts would work well, or you can leave the nuts out altogether.

Chocolate Topping

White and Dark Chocolate

To create the marbled effect, you’ll need both dark and white chocolate. I recommend using dark baking chocolate with approximately 45% cocoa and white baking chocolate. For a more intense flavour, you can use chocolate with up to 80% cocoa.

If you don’t enjoy the sweetness of white chocolate, you could just use dark chocolate and forgo the marbled effect.

Detailed Instructions

Step 1: Prepare Your Equipment

Preheat your oven to 160^oC (320°F) fan forced. Grease and line an 18x28cm (7×11 inch) slice tin. I recommend using compostable baking paper for an eco-friendly option that works just as well as regular baking paper.

I also like using this rose gold slice tin from Wiltshire. It’s perfect for making this indulgent chocolate caramel slice and has quickly become one of my favourite kitchen tools.

Step 2: Make the Biscuit Base

In a food processor, blend the flour, baking powder, brown sugar, butter, and almond meal until the mixture resembles breadcrumbs. Add the melted chocolate and process again to form a smooth dough.

Step 3: Bake the Biscuit Base

Press the mixture firmly into the prepared tin using the back of a metal spoon. Then prick with a fork a few times.

Bake for 15 minutes or until the top starts to feel firm. Keep a close eye on it, as dark chocolate makes it harder to judge if something is ready based on colour. Set aside to cool while you prepare the caramel.

Step 4: Make the Caramel

In a medium saucepan, combine the condensed milk, golden syrup, butter, and caster sugar. Cook over a medium-low heat, stirring constantly until smooth and golden.

Step 5: Finish the Hazelnut Caramel Layer

Stir in the toasted hazelnuts, then pour the caramel over the cooled base. Refrigerate for 1 hour or until firm.

Note: If toasting the hazelnuts yourself, you should do this before making the caramel. Raw hazelnuts can be toasted in the oven for 5 minutes at 160°C.

Step 6: Top with Chocolate

Dot spoonfuls of the melted dark chocolate onto the caramel layer, leaving 2cm gaps between each. Fill the gaps with the melted white chocolate. Then use a small palette knife to swirl the chocolates together in a zig-zag motion to create a marbled effect.

Step 7: Chill the Chocolate Caramel Slice

Refrigerate the slice for at least two hours to allow the chocolate to set. Before cutting, let the slice sit at room temperature for about 10 minutes to prevent the chocolate from cracking. Cut the slice into small squares or bars to serve.

Serving Suggestions

I love pairing this sweet treat with a cup of green tea, which complements the rich caramel and chocolate perfectly. Of course, it’s just as good on its own!

Storage Tips

Store the slice in an airtight container in the fridge. It can be left at room temperature for a few hours, but refrigeration is best for long-term storage, especially in warm or humid climates. Before cutting, allow the slice to sit at room temperature for about 10 minutes to prevent the chocolate from cracking.