This light and moist chocolate orange cake recipe with chocolate buttercream flavoured with fresh orange juice is an easy bake that looks impressive. I have made this cake so many times over the years, I really think it is the best chocolate cake recipe and hope you will think so too!

This chocolate & orange cake is my go to recipe, whether for birthdays, to take to a friends or for afternoon tea. Chocolate and orange is one of our favourite flavour combinations, from this eggless chocolate orange drizzle cake to chocolate orange cupcakes, so it seemed about time to share this chocolate orange cake recipe.
Jump to:
Why we love this recipe
- This easy chocolate cake stays moist for days, thanks to the use of oil in the cake.
- Using milk mixed with vinegar makes a homemade buttermilk, which not only makes a cake light and moist, but soft too.
- Made with fresh orange juice and fresh orange zest, the orange flavour is more subtle than if you use an artificial flavouring which can easily overpower the cake.
- Although I have topped the chocolate sponge with a simple buttercream for these photos (and included the buttercream recipe in the post) this cake can be served plain or with a plain chocolate buttercream and is equally delicious.
- It is a great birthday cake recipe. I have made my son’s birthday cake with this recipe for the past 2 years, as I wanted a cake that I could make a day or two before and would still taste delicious on the day itself (and a recipe that wasn’t dry to begin with!)
Ingredients notes and substitutions
- Flour – plain flour or all purpose flour
- Unsweetened cocoa powder – I prefer to use a dutch processed cocoa powder for the deepest colour and chocolate flavour. In Australia I like to use Nestle Plaistowe cocoa premium. However this is a personal preference and if you want to use a more budget friendly cocoa powder the cake will still be packed with chocolate flavour and delicious 🙂
- Fresh orange – The whole orange is used in the recipe – the orange juice and orange zest are both used to flavour the cake, and the buttercream. I don’t recommend using an artificial orange flavour in this cake.
- Oil – a neutral oil or light olive oil work in this cake. You don’t want to use a heavy olive oil though as you will be able to taste it.
- Sugar – soft brown sugar creates a moist cake.
- Egg – this recipe just needs 1 egg.
- Baking powder and baking soda – using both of these leavening agents provides the fluffiest, lightest cake.
- White vinegar – to make the homemade buttermilk. You can use lemon juice or rice wine vinegar instead.
- Milk – I use full fat cows milk, however you can use half fat milk if you prefer.
- Vanilla – vanilla bean paste or vanilla essence. I find adding a touch of vanilla helps the chocolate flavour.
- Buttercream – is made with softened butter, orange juice and zest and cocoa powder.
How to make this chocolate & orange cake
For full detailed recipe please scroll to the recipe card at the end of the post.
- Mix the milk with vinegar in a small bowl or jug and put to one side.
- In a large mixing bowl, whisk the plain flour with the bicarbonate of soda / baking soda, baking powder, cocoa powder, sugar and orange zest.
- Mix the vineger-milk with the oil, egg and vanilla.
- Add the wet ingredients to the dry ingredients and stir with a spoon.
- Pour in the 120ml (½ c) boiling water and orange juice and mix with a spoon until just combined. It doesn’t matter if there are lumps of flour in the batter.
- TIP: the batter can have a few lumps in – this is OK! See image below.
- Pour into the lined baking tin.
- Place the cake into the preheated oven and bake for 30-35 minutes until a skewer inserted into the middle of the cake comes out clean.
How to make the chocolate orange buttercream
- Beat the softened butter with the orange zest.
- Sift in the icing sugar / confectioners sugar and cocoa powder then mix.
- Add the orange juice and mix to combine. Add a little more orange juice (or milk) if the buttercream seems too thick. You should be able to easily run a spoon through it and leave the trail (see image below)
- Spread the buttercream over the top of the cold cake. Use a spatula or blunt knife to do this.
FAQ
The best way to add orange flavour to baking is to use the zest of the orange as this contains oils that are packed with orange flavour. Don’t use the white layer underneath the zest (the pith) as this tastes bitter.
You can use ready squeezed orange juice, but make sure it is 100% orange juice. As this particular recipe also uses the zest I do think it’s worth buying a fresh orange. However if you can’t get a fresh orange then use ready squeezed.
My recipe tips
- Beating the orange zest in with the butter and sugar helps release the oil and therefore the orange flavour, throughout the cake.
- Don’t over mix the batter – it is better to have a few small lumps of flour in the batter.
- It’s easier to zest the orange before you juice it, and I find a microplane grater is awesome for grating citrus.
- When zesting the orange take care not to grate the white part – the pith – as this is bitter.
- If the buttercream is too thick when you ice the cake it can pull crumbs off the top of the cake which can get mixed into the buttercream and look messy.
Storage
- Iced – the cake will keep in an airtight container for up to 3 days.
- Un-iced – the cake should keep for up to 5 days in an airtight container at room temperature unless it is very humid, in which case it will not keep quite as well, for up to 3-4 days.
Variations
- If you are lucky enough to have some leftover Terry’s chocolate orange in the house, roughly chop up ½ one and fold through the batter before you cook it. Terry’s chocolate orange segments would also be a fun and striking way to decorate the cake.
- Dairy free orange chocolate cake – use a dairy free milk for the cake and a dairy free spread for the chocolate orange buttercream or leave the cake un-iced.
More easy chocolate recipes
Chocolate Orange Cake
Author: Robyn
Equipment
- 19cm (7½ ") round tin
Ingredients
- 120ml (½ c) milk ($0.20 / £0.09)
- 1 teaspoon white vinegar ($0.03 / £0.01)
- 110g (¾ c) plain flour ($0.14 / £0.07)
- 1 teaspoon baking soda / bicarbonate of soda ($0.03 / £0.02)
- ½ teaspoon baking powder ($0.05 / £0.02)
- 40g (⅓ c) unsweetened cocoa powder ($0.43 / £0.21)
- 125g (½ c + ⅛ c) soft brown sugar ($0.43 / £0.20)
- ½ orange, zested ($1.10 / £0.30)
- 60ml (¼ c) neutral oil ($0.32 / £0.11)
- ½ orange, juiced –
- boiling water added to orange juice to make 120ml / ½ c ($0 / £0)
- 1 egg, beaten ($0.35 / £0.18)
- ½ teaspoon vanilla essence or bean paste ($0.02 / £0.01)
Chocolate orange buttercream
- 75g (⅓ c) butter, softened ($0.98 / £0.53)
- 160g (1⅓ c) icing sugar / confectioners sugar ($0.58 / £0.34)
- 3 tablespoons unsweetened cocoa powder ($0.49 / £0.24)
- ¾ teaspoons orange zest –
- 1½ tablespoons orange juice –
Instructions
- Preheat the oven to 160˚C fan / 180˚C / 320˚F convection / 356˚F.
- Line a 19cm (7½ ") round tin with baking paper / baking parchment.
- In a small bowl mix the milk with the vinegar and set to one side.
- In a large mixing bowl, whisk the plain flour with the bicarbonate of soda / baking soda, baking powder, cocoa powder, sugar and orange zest.
- Whisk the milk with the oil, egg and vanilla with a fork.
- Add the wet ingredients to the dry ingredients and mix to just combine.
- Pour in the 120ml (½ c) water and orange juice and mix until just combined. It doesn't matter if there are lumps of flour in the batter.
- Pour into the lined baking tin.
- Place the cake into the preheated oven and bake for 30-35 minutes until a skewer inserted into the middle of the cake comes out clean.
- Leave to cool in the tin for 5 minutes before turning out on to a wire rack to cool completely.
To make the chocolate orange buttercream
- Beat the softened butter with the orange zest.
- Sift in the icing sugar / confectioners sugar and cocoa powder then mix to start to combine (it will look crumbly).
- Add the orange juice and mix to combine. Add a little more orange juice or a little milk if the buttercream seems too thick.
- Spread the buttercream over the top of the cold cake.
- Serve. Store any leftovers in an airtight tin for up to 3 days.
Notes
Nutrition
HAVE YOU MADE THIS RECIPE?
I’d love to see your creation!
Or just leave a comment below!
Let me know your thoughts!