Desserts
Chocolate Pistachio Cake with Pistachio Ganache
At a Glance
- Prep
- 25 min
- Cook
- 35 min
- Serves
- 12
- Difficulty
- Medium
Equipment at a Glance
- Two 23cm (9-inch) round cake tins
- Mixing bowls
- Whisk & electric mixer
- Saucepan for ganache
- Wire cooling racks
Pro Tip
Cool the cake layers completely before adding the ganache, and allow the ganache to thicken to a spreadable consistency before assembly.
Introduction
Hot coffee goes into this batter near the end, not for a coffee flavour, but because hot liquid blooms the cocoa and deepens the chocolate taste without the cake tasting of coffee at all. The pistachio ganache then goes on only once the sponge layers are completely cool — even slight warmth softens the ganache and makes neat stacking much harder.
Allow about 25 minutes to prepare and 35 minutes to bake, plus time to cool and assemble. It serves twelve.
What You'll Need
Equipment
Two 23cm round cake tins, greased and lined, are what this recipe is built around; a different tin size will change the baking time.
Ingredients
For the sponge
- 2 cups plain flour
- 2 cups granulated sugar
- ¾ cup unsweetened Dutch-process cocoa powder
- 2 tsp baking powder
- 1½ tsp bicarbonate of soda
- 1 tsp salt
- 2 large eggs, room temperature
- 1 cup whole milk
- ½ cup vegetable oil
- 2 tsp vanilla extract
- 1 cup hot brewed coffee (or near-boiling water)
For the pistachio ganache
- 1 cup heavy cream
- 8 oz white chocolate, chopped
- ½ cup unsweetened pistachio paste
- ½ cup toasted pistachios, finely chopped, to garnish
Dutch-process cocoa gives a deeper colour and a smoother, less acidic flavour than natural cocoa. Use unsweetened pistachio paste rather than a sweetened pistachio spread, since the sugar balance in the ganache is built around it being unsweetened.
How to Make Chocolate Pistachio Cake
Mix and Bake the Sponge
- Preheat the oven to 175°C (350°F). Grease the two cake tins and line the bases with baking parchment. Whisk together the flour, sugar, cocoa powder, baking powder, bicarbonate of soda and salt in a large bowl. Add the eggs, milk, oil and vanilla, and mix on medium speed for 2 minutes until smooth.
- With the mixer on low, slowly pour in the hot coffee — the batter will turn noticeably thin, which is what keeps the finished cake moist. Divide evenly between the tins and bake for 30–35 minutes, until a skewer inserted in the centre comes out clean or with a few moist crumbs. Cool in the tins for 10 minutes, then turn out onto wire racks to cool completely before adding any ganache.
Make the Pistachio Ganache
- Heat the cream in a small saucepan over medium heat until just steaming at the edges — don't let it boil. Pour it over the chopped white chocolate and leave for 2 minutes, then whisk gently until melted and smooth. Stir in the pistachio paste and leave the ganache to cool for about 20 minutes, stirring occasionally, until it thickens to a spreadable consistency.
Chill or Set
- Once the cake layers are completely cool, place one on a serving plate and spread an even layer of ganache on top. Add the second layer, then spread the remaining ganache over the top and sides. Scatter with the toasted chopped pistachios. Chill for 15–20 minutes before slicing, for cleaner layers.
Tips for the Best Results
- Let the layers cool completely before touching the ganache
- Even mild warmth softens it and makes the cake harder to stack neatly.
- Don't rush the ganache
- It needs about 20 minutes to thicken from a pourable mixture into something spreadable — trying to use it too soon means it runs off the sides. If it still feels loose after cooling, give it a few more minutes rather than adding extra chocolate.
- Pour the coffee in slowly with the mixer running
- This keeps it incorporated evenly rather than pooling at the bottom of the bowl.
- Use an even hand with the ganache between layers
- Spreading it evenly, rather than pushing extra towards the edges, keeps the layers level and stops them sliding apart when you slice.
- Check doneness with a skewer, not just the clock
- Measure the cocoa, baking powder and bicarbonate of soda accurately, and confirm the centre is fully set before taking the cake out — an underbaked centre is the main cause of a sunken or dense sponge.
How to Store and Freeze Chocolate Pistachio Cake
Store the cake in an airtight container in the fridge for up to 5 days, since the ganache contains cream. Let refrigerated slices stand at room temperature briefly before serving, so the sponge and ganache soften slightly.
Individual slices can be wrapped and frozen for up to 2 months. Thaw overnight in the fridge, then bring to room temperature before serving.
Substitutions and Variations
- More pistachio
- scatter extra toasted, chopped pistachios over the finished ganache for a stronger pistachio presence.
- Sharper contrast
- a light sprinkling of flaky sea salt over the ganache cuts through the sweetness of the white chocolate.
- Make ahead
- bake and cool the sponge layers completely, then wrap well and store until you're ready to assemble — add the ganache only once the layers are completely cool.
Frequently Asked Questions
- Where can I find pistachio paste?
- Pure pistachio paste is available from specialist food shops and online retailers. You can also make it by processing shelled pistachios until smooth, though the texture depends on the nuts and equipment used.
- Why is my pistachio ganache too runny?
- It's probably still too warm — let it cool and thicken before assembling the cake. If the ingredient ratios were changed, that can also affect the final consistency.
- Can I make the cake layers ahead?
- Yes. Bake and cool the layers completely, then wrap them well and store until assembly. Add the ganache only once the layers are completely cool.
Reviews (0)