Butter Bars Recipe

100 g/4 oz butter or margarine, softened
100 g/4 oz caster (superfine) sugar
1 egg, separated
100 g/4 oz/1 cup plain (all-purpose) flour
25 g/1 oz chopped mixed nuts

Method:

Cream together the butter or margarine and sugar until light and fluffy. Blend in the egg yolk, then stir in the flour and nuts to make a fairly stiff mixture. If it is too stiff, add a little milk; if it is runny, stir in a little more flour. Spoon the dough into a greased 30 x 20 cm/12 x 8 in Swiss roll tin (jelly roll pan). Beat the egg white until frothy and spread over the mixture. Bake in a preheated oven at 180°C/ 350°F/gas mark 4 for 30 minutes until golden. Leave to cool, then cut into bars.