Boozy rhubarb and custard tart

INGREDIENTS

For the pastry

    3 large free-range egg yolks and 1 egg white for brushing
    85g unsalted butter, cut into chunks
    85g caster sugar
    Grated zest of 1 lemon
    170g plain flour, plus extra for dusting

For the filling

    9 large free-range egg yolks (see tip)
    1 tsp vanilla extract
    60g caster sugar
    500ml whipping cream

For the jelly

    3 gelatine leaves (see Know-how)
    300ml rhubarb liqueur (we used Chase, from online retailers)
    A few drops of pink food colouring
    Handful of rhubarb and custard sweets to decorate

METHOD

    01.To make the pastry, whizz the 3 egg yolks and butter in a food processor until light and fluffy. Gradually pulse in the 85g sugar, then the lemon zest, and finally the flour with a pinch of salt, pulsing just until the pastry comes together. Turn out onto a lightly floured surface and bring the dough together gently and quickly with your hands (it will be soft). Press into a flattish disc, wrap in cling film and chill in the fridge for 1 hour.
    02.Once chilled, roll the pastry out to the thickness of a £1 coin and use to line a 23cm fluted loose-bottomed tart tin, pressing the pastry into the corners so they’re sharp. Roll the rolling pin over the top of the case to trim the excess, then go around the tart case pressing the pastry into the top of each flute so it’s secure. Chill again for 30 minutes in the fridge, or in the freezer for 15 minutes.
    03.Preheat the oven to 190°C/fan170°C/gas 5. When the pastry case is firm, line with foil or baking paper, fill to the brim with baking beans or rice and blind bake for 20 minutes, then remove the beans/rice and foil/paper. Turn down the oven to 170°C/fan150°C/gas 3½ and cook for another 5-10 minutes until the pastry is golden, dry and crisp.
    04.Brush the egg white all over the inside of the pastry, filling in any cracks, then return to the oven for 5 minutes to firm up and seal the case. Leave to cool completely. Turn the oven down to 130°C/fan110°C/gas ¾.
    05.To make the filling, stir the 9 egg yolks with the vanilla extract and 60g caster sugar until well combined, then pour over the whipping cream. Stir to combine, then strain into a pan and heat very gently until the mixture is at blood temperature. Pour into the tart case, burst as many bubbles as you can on the surface, then put the tart on a baking sheet. Transfer to the middle shelf of the oven and bake for 30-40 minutes until set but still with a gentle wobble when you move it. Remove from the oven and allow to cool completely.
    06.To make the jelly, soak the gelatine leaves in cold water until soft, then squeeze the water out and put in a pan with 100ml of the rhubarb liqueur. Heat very gently, stirring just to melt the gelatine, then strain into a bowl containing the remaining liqueur mixed with a little food colouring. Stir, then let the tart and the jelly mix cool completely (the jelly will be liquid at room temperature). Pour the jelly over the tart and leave to set overnight in the fridge.
    07.An hour before serving, remove the tart from the fridge and put it somewhere cool to allow it to reach room temperature. Just before serving, put the rhubarb and custard sweets in a plastic freezer bag and bash with a rolling pin until they shatter into small shards. Scatter them over the top of the tart, then slice and serve.