Method

1. Sift the icing sugar into a large bowl. Add the softened butter and lemon zest and beat using an electric whisk until smooth. Add 3 of the egg yolks and beat until incorporated. Add the flour and ¼ tsp salt and mix again until starting to clump together. Bring together into a ball using your hands. Cover and put in the fridge to rest for 30 mins.

2. For the filling combine the eggs, sugar and lemon juice (you should have around 100ml) and zest in a bowl, then whisk together. Add the cream and use a hand blender to blend fully, trying not to add too much air. Cover and set aside in the fridge.

3. Remove the pastry from the fridge and leave for 5 mins before rolling to avoid any cracking. Lightly dust a work surface with flour and roll out the pastry to a 3mm-thick circle. Use the rolling pin to lift the pastry into a 23cm loose-bottomed tin, gently pressing into the base and sides. Trim off the excess pastry, then roll some of the excess into a ball and use it to gently push the pastry into the creases of the tin. Prick the pastry with a fork and chill for 30 mins.

4. When ready to bake, heat the oven to 190C/170C fan/gas 5. Scrunch up a sheet of baking parchment and line the pastry with it, then fill with baking beans. Blind-bake the pastry for 20 mins until the base is just set. Carefully remove the baking parchment and beans, then bake for a further 10-15 mins until golden. Beat the remaining egg yolk, brush over the base and sides of the pastry to seal and return to the oven for 1 min. Remove from the oven and reduce the temperature to 150C/130C fan/gas 2.

5. Remove the filling from the fridge and pour into a saucepan. Heat gently over a low heat until the mixture reaches 40C (check with a thermometer), then transfer to a jug. Put the pastry case on a baking tray and pour in half the filling. Transfer to the oven then, while on the oven rack, pour in the remaining filling. Bake for 25-30 mins until set around the outside but with a slight wobble in the middle. Remove from the oven and leave to cool to room temperature before chilling in the fridge for at least 2 hrs. To serve, transfer to a plate and dust with icing sugar.