Ingredients:
For the pastry:
175g plain flour
100g cold butter , cut in small pieces
1 tbsp icing sugar
1 egg yolk
OR 375g pack sweet shortbread pastry
For the filling:
juice and zest 3 lemons
juice and zest 3 limes
150g (5oz) caster sugar
50g (2oz) cornflour
200ml (7fl oz) water
5 egg yolks
15g (½oz) unsalted butter
For the meringue:
5 egg whites
100g (4oz) caster sugar
Method:
You will need 23 x 3cm (9 x 1¼in) deep tart tin.
1. For the pastry, put the flour, butter, icing sugar, egg yolk (save the white for the meringue) and 1 tbsp cold water into a food processor. Using the pulse button so the mix is not overworked, process until the mix starts to bind. Tip the pastry onto a lightly floured surface, gather together until smooth, then roll out and line a fluted flan tin. Trim and neaten the edges. Press pastry into flutes. The pastry is quite rich, so don’t worry if it cracks, just press it back together. Prick the base with a fork, line with foil, shiny side down, and chill for 1⁄2-1 hour (or overnight). Preheat the oven to 200 C, 180 C fan oven, 400 F, gas 6. Bake for 10 minutes or until lightly golden, then remove the foil and bake for a further 5 minutes. Allow to cool.
2. To make the filling, place the juice (you should have 300ml (½pt) of liquid – if not, make it up by squeezing in some more juice), zest and sugar in a pan and heat until the sugar is dissolved. Mix the cornflour to a paste with 3 to 4 tbsp of the water and add to the juice in the pan along with the remaining water. Bring to the boil, stirring all the time. Cool slightly and whisk in the egg yolks and butter. Pour the filling into the pastry case. Lower the oven to 180C/fan 160C/gas 4. Bake for 15-20 minutes.
3. To make the meringue, whisk the egg whites until they form soft peaks, then add one third of the sugar. Whisk for a further minute and add a third more sugar. Whisk for another minute and add the last of the sugar. The mixture should be smooth, thick and glossy. Spoon the meringue over the filling covering it completely, then swirl it with the back of the spoon. Bake for another 10 to 15 minutes until the meringue is golden; serve cold.
