Cut the pastry into 6, then roll one portion out between 2 sheets of clingfilm until a little larger than a buttered individual 10 cm (4 inch) loose-bottomed fluted tart tin. Remove one sheet of clingfilm, lay the pastry over the tin, then remove the top sheet of clingfilm. Press the pastry into the base and sides of the tin with fingers dusted with rice flour. Trim off the excess pastry with scissors so that it stands a little above the top of the tin. Patch any cracks or breaks with pastry trimmings. Repeat to make 6 tarts. Prick the bases with a fork, then chill for 15 minutes.
Bake the tarts blind (see
Mix the condensed milk, egg yolks, lemon rind and juice together in a bowl until the mixture thickens, then spoon the filling into the tart cases. In a second bowl, whisk the egg whites until stiff, then gradually whisk in the sugar, a little at a time until very thick and glossy.
Spoon the meringue over the lemon filling and swirl with the back of a spoon into peaks. Bake for 10–15 minutes until the meringue peaks are golden and just set. Leave to stand for 5 minutes, then remove from the tins and serve warm or cold with cream.