Gluten-Free & Dairy-Free Chocolate Orange Marble Cake

Chocolate orange is one of those combinations that just works. This gluten-free and dairy-free chocolate orange cake is rich, moist and full of fresh orange flavour, with ribbons of dark chocolate running through a soft orange sponge.

It’s topped with a glossy chocolate-orange ganache, but you can absolutely leave the ganache off and simply dust the cake with icing sugar if you want something a little simpler.

The best thing? You wouldn’t know it’s gluten and dairy free.

You will need

For the cake

• 250g dairy-free baking block, softened
• 225g caster sugar
• 250g gluten-free self-raising flour
• 4 large eggs, at room temperature
• 2 large oranges
• 1 tsp vanilla extract
• 2 tbsp fresh orange juice
• 25g good-quality gluten-free and dairy-free cocoa powder
• 1 tsp espresso powder, optional
• 75g dairy-free dark chocolate, finely chopped
• 2–3 tbsp dairy-free milk, if needed
• ½ tsp xanthan gum, only if your gluten-free flour blend doesn’t already contain it
• Small pinch of sea salt

For the chocolate-orange ganache

• 150g good-quality dairy-free dark chocolate
• 150ml dairy-free cream alternative, suitable for whipping or cooking
• 1 tbsp dairy-free butter
• 1 tsp finely grated orange zest
• 1 tsp fresh orange juice
• ½ tsp orange extract or a few drops of food-grade orange oil, optional

To decorate

• Finely grated orange zest
• Dark chocolate shavings
• Flaky sea salt, optional
• Icing sugar, optional

Before you start

Preheat your oven to 180°C / 160°C fan / Gas Mark 4.

Grease a 20cm square cake tin or 900g loaf tin and line it with baking parchment.

Check your gluten-free flour before adding xanthan gum. Many ready-made gluten-free flour blends already contain it, so you don’t want to add extra unnecessarily.

It’s also worth checking every packaged ingredient carefully if you’re baking for someone with coeliac disease or a severe allergy. Look for products labelled gluten free and check for any relevant allergen warnings.

How to make the cake

Finely grate the zest from both oranges, keeping a little aside for decorating.

Put the softened dairy-free butter and caster sugar into a large mixing bowl and beat for 3–4 minutes, until pale, light and fluffy.

Add the eggs one at a time, beating well after each addition. If the mixture looks slightly curdled, don’t worry – the flour will bring it back together.

Add the vanilla, two tablespoons of fresh orange juice and most of the orange zest.

Sift in the gluten-free self-raising flour and gently fold it through the mixture.

Add the xanthan gum at this stage if your flour doesn’t already contain it, along with the small pinch of sea salt.

The mixture should be soft and easily spoonable. Gluten-free flour can sometimes absorb more moisture than regular flour, so if your batter seems particularly thick, add a tablespoon of dairy-free milk at a time until it reaches the right consistency.

Make the chocolate batter

Spoon roughly one-third of the cake mixture into a separate bowl.

Add the cocoa powder, espresso powder if using, and chopped dairy-free dark chocolate.

Fold gently until combined.

If the chocolate mixture is much thicker than the orange mixture, add another tablespoon of dairy-free milk to loosen it.

The espresso powder is optional, but it won’t make the cake taste like coffee. It simply deepens the chocolate flavour.

Create the marble effect

Spoon approximately half of the orange batter into your prepared tin.

Add the chocolate mixture through the middle and then cover with the remaining orange batter.

Take a skewer or the handle of a teaspoon and gently swirl it through the mixture a few times.

Don’t overdo it. You want those lovely ribbons of chocolate running through the orange sponge rather than one completely mixed-up brown cake.

Bake

Place the cake in the centre of the oven and bake for approximately 45–50 minutes.

Gluten-free cakes can sometimes need a little longer than their traditional counterparts, so don’t worry if yours takes a few extra minutes.

The cake should be risen and golden and should feel lightly springy when pressed in the centre.

Insert a skewer into the middle. It should come out clean or with a few moist crumbs attached.

If the top is browning too quickly, loosely cover it with foil for the final 10–15 minutes.

Leave the cake in the tin for around 10–15 minutes, then carefully transfer it to a wire rack to cool completely.

Gluten-free cakes can be a little more delicate while they’re warm, so resist the temptation to cut into it straight away.

Make the chocolate-orange ganache

Once the cake is completely cool, make your ganache.

Finely chop the dairy-free dark chocolate and put it into a heatproof bowl.

Warm the dairy-free cream alternative in a saucepan over a low-medium heat until hot and steaming, but don’t let it boil.

Pour it over the chocolate and leave it for around 3 minutes.

Then slowly stir from the centre outwards until you have a smooth, glossy ganache.

Add the dairy-free butter, orange zest and orange juice and stir until completely smooth.

If you’re using orange extract or food-grade orange oil, add just a tiny amount. It’s surprisingly powerful.

Leave the ganache to cool and thicken for around 15–20 minutes, stirring occasionally, until it’s thick enough to spread over the cake.

Decorate

Spread the ganache over the cooled cake, letting a little fall naturally over the edges.

Finish with finely grated orange zest and a few dark chocolate shavings.

For a slightly more grown-up finish, add a very small pinch of flaky sea salt.

Or keep things simple and dust the cake with icing sugar.

A few important gluten-free and dairy-free tips

Check your chocolate. Not all dark chocolate is dairy free, and products can have different allergen warnings. Choose one that’s clearly labelled suitable for your needs.

Check the cocoa powder too. Pure cocoa powder is naturally gluten free, but cross-contamination can be an issue with some products.

Don’t automatically add xanthan gum. Check your flour blend first. Many gluten-free self-raising flours already contain it.

Don’t overmix once the flour goes in. Gently folding is enough.

Let it cool properly. Gluten-free cakes can be more fragile when warm, so give it time to firm up before decorating or slicing.

Use a dairy-free baking block rather than a soft spread if possible. The blocks tend to behave more like butter when baking and give you a better texture.

Can I make it without the ganache?

Absolutely.

The cake is full of enough chocolate and orange flavour to stand on its own.

For a simple finish, allow it to cool completely and dust with icing sugar.

Or serve it with dairy-free whipped cream, coconut cream or a scoop of dairy-free vanilla ice cream.

A little fresh orange zest over the top makes it look beautiful without requiring much effort.

How long will it keep?

Keep the cake in an airtight container at room temperature for around 3–4 days.

If you’ve used a dairy-free cream alternative in the ganache, follow the storage instructions for that particular product. If it needs refrigeration, keep the finished cake chilled and bring it back towards room temperature before serving.

You can also freeze the un-iced cake. Wrap it well and freeze for up to 3 months. Defrost thoroughly before decorating.

And the important bit…

Nobody needs to know it’s gluten and dairy free.

You’ve still got that lovely combination of buttery-tasting orange sponge, rich dark chocolate, fresh orange zest and a glossy chocolate topping – just without the gluten or dairy.

It’s the sort of cake that works for a birthday, afternoon tea, a dinner party or simply because you’ve got oranges sitting in the fruit bowl and fancy making something.

And honestly, chocolate orange cake is never going to be a bad idea.

Especially when you can have another slice without having to explain why you made a “free-from” cake.

It’s just cake.

Really good cake.