Ingredients

Step by step

1. For the pastry, cream both sugars and the butter in a mixing bowl until pale and fluffy. Beat in 3 of the egg yolks, one at a time. Sift over the flour with a pinch of salt and mix until combined. Bring the dough into a ball and flatten into a round. Wrap and chill for at least 4 hours, or overnight.

2. Take the pastry out of the fridge and allow it to soften. Butter and flour a 23cm-diameter fluted tart tin (about 3cm deep), shaking out the excess flour. Roll the dough out on a floured surface to a thickness of 3mm and use it to line the tart tin, pressing it into the edges and leaving a slight overhang. Chill again for at least 1 hour, or freeze for 30 minutes.

3. Preheat the oven to 180°C, fan 160°C, gas 4. Line the chilled tart case with baking paper and baking beans. Bake for 15 minutes or until the edges are golden brown. Remove the paper and beans and bake for a further 8-10 minutes, or until golden brown all over. Remove from the oven. Lightly beat the reserved egg yolk and brush over the tart case to seal any holes or cracks. Place the tin on a cooling rack and leave to cool completely. Turn the oven down to 120°C, fan 100°C, gas ½.

4. For the custard filling, slit the vanilla pod lengthways and scrape out the seeds. Put the seeds and pod into a pan with the double cream and bring slowly to the boil. In a large bowl, whisk the egg yolks and sugar together for just 1 minute. Pour the boiling cream over the mixture, whisking constantly. Pass through a fine sieve into a bowl, then pour the warm custard into the tart case. Bake for about 18 minutes, then carefully turn the tart round and bake for a further 9-11 minutes, or until there is only a small wobble in the centre of the tart. Remove from the oven and cool completely on a wire rack.

5. For the rhubarb topping, preheat the oven to 160°C, fan 140°C, gas 3. Place the rhubarb lengths in an oven dish, sprinkle over the sugar and pour over the orange juice. Cover loosely with foil and roast for 18–22 minutes, until the rhubarb is very tender but still holding its shape. Leave to cool for 5-10 minutes, then carefully lift the rhubarb from the dish and set aside. Strain the roasting juices into a small pan; you should have approximately 150ml. Warm gently until just steaming, then remove from the heat. Meanwhile, soak the gelatine in cold water for 5 minutes. Squeeze out the excess water from the gelatine and whisk it into the warm rhubarb juices until dissolved. Arrange the roasted rhubarb over the cooled custard tart, trimming to fit as necessary. Spoon the warm jelly evenly over the rhubarb. Chill for 2–3 hours, or until the topping has set. Cut into slices to serve.