Lemon squares

MAKES 30

125 g (4½ oz/½ cup) unsalted butter, softened

75 g (2½ oz) caster (superfine) sugar

155 g (5½ oz/1¼ cups) plain (all-purpose) flour, sifted

icing (confectioners’) sugar, sifted, for dusting

TOPPING

4 eggs, lightly beaten

230 g (8¼ oz/1 cup) caster (superfine) sugar

60 ml (2 fl oz/¼ cup) lemon juice

1 teaspoon finely grated lemon zest

30 g (1 oz/¼ cup) plain (all-purpose) flour, sifted

½ teaspoon baking powder, sifted

1  Preheat the oven to 180°C (350°F/Gas 4). Lightly grease a 20 x 30 cm (8 x 12 inch) baking tin and line the base with baking paper, extending the paper over the long sides for easy removal later.

2  Cream the butter and sugar in a medium bowl using electric beaters until pale and fluffy. Fold in the flour with a metal spoon. Press into the prepared tin and bake for 20 minutes, or until golden and firm. Set aside to cool.

3  To make the topping, beat the eggs and sugar in a large bowl with electric beaters for 2 minutes, or until pale and thick. Stir in the lemon juice and zest. Gradually add the flour and baking powder and whisk until combined. Pour onto the base and smooth the surface with a spatula. Bake for 25 minutes, or until just firm. Cool in the tin. Dust with the icing sugar, cut into pieces and serve.