heston blumenthal’s exploding chocolate gateau
AKA Heston’s chocolate and passion fruit popping candy cake.
At New year I treated myself to Heston’s popping candy cake, which costs an absolute fortune, even on half price sale, but the results were amazing: bitter, sweet, chocolatey and of course popping! I was contemplating recreating it when it pops up on How To Cook Like Heston.
With my sister popping over for dinner this was the perfect opportunity to try it out. It had the desired reaction: one mouthful in and my niece squeals with surprise as the popping candy kicks in. The next few minutes are spent with people making ‘o’ shapes with their mouths, allowing the candy to echo round the room. Great fun.
Heston’s version has some crazy paint-gun antics; I skipped that and just shaved some dark chocolate on top instead. There’s also some madness involving rings and baking trays but I strolled past all that using a springform tin instead.
It was really close to the supermarket version. Making it again I would skew the chocolate ratio and add more milk chocolate, it was a shade too bitter. Maybe using better quality passion fruit would help. I’d also modify the base slightly – when I’ve made popping candy cakes before I used hazelnuts and I think they work really well here.
Heston Blumenthal’s exploding chocolate cake (serves 10):
For the base
30g unsalted butter, melted
2 tablespoons white caster sugar
25g popping candy
For the chocolate ganache
175g double cream
Pinch of salt
Pulp from 6 passion fruits
110g dark chocolate, plus a little more for decoration
50g milk chocolate
- Preheat the oven to 180ºC. Place the shortbread biscuits on a baking tray and bake in the oven for 10 minutes until golden brown.
- Whizz the biscuits in a food processor with melted butter and sugar.
- Gently stir in the popping candy. Place the mixture inside a 21cm springform tin. Flatten using the back of a spoon then put in the freezer to set.
- Add the cream, salt and passion fruit to a small saucepan and place over a medium heat. When it comes to the boil remove from the heat and allow to stand for 5 minutes, then stir in the custard.
- Melt the dark and milk chocolate together. Strain the infused cream and add to the bowl of melted chocolate a third at a time, making sure to incorporate the cream thoroughly after each addition. Allow the ganache to cool to room temperature.
- Use a pastry brush to spread some of the ganache on top of the biscuit base and around the edges then place in the freezer for 5 minutes. This will ensure that the ganache will not seep through (great tip!). After 5 minutes, pour the remaining ganache into the ring and place the tart in the freezer for 4 hours.
- Place a slab of dark chocolate on a chopping board and drag a large knife across it to create shavings. Top the cake with these decorations and return to the freezer.
- Remove the cake from the freezer 1 hour before serving.