Tonka bean is redolent of vanilla and marzipan, with a hint of clove, and has a particular affinity with custard. Their slightly bitter flavour complements the sweet custard and gives a new lease of life to a beloved classic bake.
Tonka beans contain coumarin, which can be toxic if consumed in high quantities, so resist the temptation to make and eat several batches a day!
Ingredients for tonka bean custard tarts Serves: 12
- 1 x 325g sheet of ready rolled puff pastry (preferably all butter)
- Soft, unsalted butter for greasing
- 1 whole medium egg
- 3 medium egg yolks
- 100g caster sugar
- 20g cornflour
- 325ml whole milk
- 2 tonka beans
Method for tonka bean custard tarts
Preheat the oven to 220°C (200°C fan). Lightly grease a 12-hole muffin tray with approx. 10g unsalted butter and refrigerate.
Take the ready rolled puff pastry out of the fridge to warm up for 10 minutes, while you make the custard.
Put 1 whole medium egg and 3 medium egg yolks into a heatproof bowl with caster sugar, cornflour and whisk to a paste.
Put the whole milk in a pan and bring to the boil. Once boiling, gradually whisk it into the egg mixture. Finely grate over 1 tonka bean and mix it in. Return the custard to the pan and whisk, over a very gentle heat, for about 5 minutes, or until the custard has thickened. Tip the custard into a jug and cover the top with clingfilm to prevent a skin forming.
Unroll the pastry and finely grate 1 tonka bean, evenly over the rectangle of pastry. Roll the pastry up its the longest side, into a fairly tight sausage. Cut the pastry into 12 equal pieces. If the pastry has become sticky, pop it in the freezer for 5 minutes. With the cut side on top, squish each spiral of pastry down flat with your hand, to form a disc. Then, use a rolling pin to gently make each disc bigger, trying to make sure you retain its roundness, until it is approx. 3mm thick, and will fit comfortably inside a muffin hole. Press each disc of pastry into the holes of the muffin tray and pop the tray into the fridge for 20-30 minutes, to allow the pastry to firm up.
Press a square of baking parchment into each hole (it’s easiest if you crumple the parchment up first) and fill each hole with baking beans. Bake the pastry cases for 8-10 minutes, then remove the beans and parchment; the pastry will still be quite raw.
Fill each hole with custard. Return the tray to the oven and bake for a further 15-20 minutes, or until the custard has fully set, with burnished spots on top and the pastry is a rich golden colour.
Leave the tarts to cool, in the tin, for 10 minutes, before transferring to a wire rack to cool completely.