This classic American Boston Cream Pie is in fact a cake. Light layers of whisked sponge filled with lashings of crème patisserie and topped with chocolate ganache create a rich and creamy slice of heaven on a plate!
Boston Cream Pie
Serves 8-10 | Preparation time 40 mins plus cooling and chilling | Baking time 25-30 mins
For the cake:
- 4 large eggs
- 250g caster sugar
- 175ml whole milk
- 30g butter
- 2 tsp vanilla extract
- 150g plain flour, sifted
- 1 tsp baking powder
- 1/2 tsp salt
- For the crème patissiere filling:
- 2 large egg yolks
- 50g caster sugar
- 25g corn flour
- 300ml whole milk
- 1 tsp vanilla bean paste or the seeds scraped from 1 pod
- For the ganache topping:
- 100g dark chocolate, chopped into small pieces
- 50ml double cream
- To prepare the crème patissiere filling, whisk the egg yolks and sugar together in a large jug until pale. Add the corn flour and whisk again until fully combined.
- Heat the milk and vanilla in a pan until just below boiling. Whilst whisking the egg mixture continuously, slowly and steadily pour the hot milk into the jug and whisk together until fully combined. Pour the mixture into the pan heating and whisking continuously until the mixture thickens and comes to the boil then continue to cook for 2 mins. Remove from the heat.
- Transfer the crème patissiere to a heatproof bowl, cover with clingfilm pressing it gently so it touches the surface of the mixture to prevent a skin from forming. Allow to cool to room temperature before chilling in the fridge for 4 hours.
- For the cake, grease and line the bases of two 20cm round cake tins and preheat the oven to 180˚C/160˚C fan/gas mark 4. Using an electric mixer, whisk the eggs and sugar until the mixture is pale and thick and almost doubled in size, this can take up to 10 mins.
- Place the milk, butter and vanilla extract in a small pan and heat gently until the butter has melted, remove from the heat and allow to cool for 10 mins. Whilst whisking the egg and sugar mixture continuously, slowly and steadily pour in the milk mixture and continue whisking until fully incorporated. Very gently fold in the flour, baking powder and salt – the flour will sink to the bottom so make sure it is fully incorporated.
- Divide the cake mixture equally between the two prepared tins and bake for 25-30 mins until golden and springy to the touch. Allow to cool in the tins for 10 mins before turning out onto a wire rack to cool completely.
- For the ganache topping, place the chocolate in a heatproof bowl. Gently heat the cream in a small pan until just below boiling then pour over the chocolate and allow to stand for 2 mins. Stir the chocolate and cream together to form a smooth glossy ganache then set aside to cool a little.
- To assemble the cake, place one layer of cake on a serving plate. Transfer the chilled crème patissiere to a bowl and whisk with a hand whisk until smooth and even. Spread the crème patissiere on top of the cake then place the other cake on top of the crème patissiere. Pour the slightly cooled ganache on top of the cake and spread evenly with a palette knife. Chill and serve.
* Crème patissiere can be made and stored in the fridge up to 3 days in advance.
* The ganache topping can also be made in advance but will need gently warming before using if it has cooled fully.