“Don’t tell your guests about the popping candy in this simple chocolate ganache gateau. Instead, sit back and watch the surprise on their faces as the base starts exploding in their mouths. This dessert recipe is the perfect excuse for getting the power tools out, namely a paint gun, which can be bought at any good hardware shop. It’s great fun to use and the effect is spectacular, but the gateau has to be frozen for it to work.” – Heston Blumenthal
Heston’s Exploding Chocolate Gateau
Preparation time: 30 minutes
Chilling time: 2 hours
Freezing time: 4 hours
150 g all-butter shortbread biscuits
30 g unsalted butter, melted
2 Tablespoons white caster sugar
25 g neutral popping candy
175 ml whipping cream
1 pinch salt
6 passionfruit, pulp only
50 ml fresh custard
110 g dark chocolate (minimum of 60% cocoa solids), broken into pieces
50 g milk chocolate, broken into pieces
500 g dark chocolate
200 ml vegetable oil
Oven temperatures are for conventional; if using fan-forced (convection), reduce the temperature by 20˚C.
We use Australian tablespoons and cups: 1 teaspoon equals 5 ml; 1 tablespoon equals 20 ml; 1 cup equals 250 ml.
All herbs are fresh (unless specified) and cups are lightly packed.
All vegetables are medium size and peeled, unless specified.
All eggs are 55 to 60 g, unless specified.
Preheat the oven to 180ÂºC/gas mark 4. Place the shortbread biscuits on a baking tray and bake in the oven for 10 minutes or until golden brown.
Place the biscuits in a food processor and add the melted butter and sugar. Blitz until the mixture resembles fine sand in texture.
Gently stir in the popping candy. Place the mixture inside a 15 cm cake tin placed on a tray lined with baking paper. Flatten using the back of a spoon then put to one side to set.
Add the cream, salt and passionfruit to a small saucepan and place over a medium heat until it almost comes to the boil. Remove from the heat and allow to stand for 5 minutes, then stir in the fresh custard.
Put the dark and milk chocolate in a heatproof bowl. Place over a bain marie (a pan of gently simmering water) and allow to melt completely. Remove from the heat.
Strain the infused cream and add to the bowl of melted chocolate, one-third at a time, making sure to incorporate the cream thoroughly after each addition. Allow the ganache to cool to room temperature.
Once the tart base has set, use a pastry brush to spread some of the ganache on top of the base and around the edges, then place in the freezer for 5 minutes. This will ensure that the ganache will not seep through.
After 5 minutes, pour the remaining ganache into the ring and place the tart in the fridge to set for 2 hours. Place the tart in the freezer for at least 4 hours before flocking.
After the gateau is fully frozen, sit the gateau on a wide upturning glass or pot. Remove the metal ring by lightly warming with a blow torch. Remove by carefully sliding the ring downwards. Place back in the freezer.
For the flocking, break the chocolate into chunks and place in a small heatproof bowl. Melt the chocolate by placing the bowl over a bain marie. Leave to cool slightly before stirring in the vegetable oil.
Fill the base of a paint gun with the melted chocolate mixture and attach the nozzle. To avoid redecorating the kitchen in chocolate brown, set a large cardboard box on its side to provide a protective roof and walls to work in.
Remove the gateau from the freezer and carefully lift it onto a plate. Place the gateau in the cardboard box then spray it with the chocolate, turning carefully as you go. Return it to the freezer until 20 minutes before serving.
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