Divide the pastry into 3 pieces and roll each one out thinly on a lightly floured surface. Use to line 3 x 12 cm (5 inch) fluted flan tins (see
Beat the butter and sugar until pale and light, then gradually beat in the eggs. Fold in the hazelnuts.
Divide the berries among the pastry cases and spoon over the hazelnut mixture, spreading it flat. Bake for 25–30 minutes or until risen and firm to the touch.
Put the jam in a small pan with the lemon juice and measured water and heat gently until the jam melts. Increase the heat and boil for 1 minute, remove from the heat and press through a fine sieve. Keep warm.
Brush the warm apricot glaze brush over the tarts as soon as they come out of the oven. Leave to cool in the tins and serve dusted with icing sugar.