This has been such a popular recipe for decades that is was featured, and probably still is, on heaps of café menus around the country. Now you can make it at home.
225g (about 8 oz) unsalted butter, softened
70g (about 2½ oz) icing (confectioner’s) sugar
275g (about 9½ oz) plain flour
400g (about 14 oz) granulated (regular white) sugar
4 medium (size 6) free-range eggs, beaten together
4 Tbsp standard flour
1 tsp baking powder
Finely grated zest 2 lemons
90ml (about 3½ fl oz) lemon juice, strained
Icing (confectioner’s) sugar for dusting
1 Preheat oven to 170°C (325°F). Put the softened butter in the bowl of a food processor and process until whipped, then add the icing sugar and process until light in colour (creamed). Sprinkle the flour over and process until the mixture starts to form a ball. Tip into a non-stick Swiss roll tin (jelly roll) tin 32 cm x 21 cm (13” x 8” approx.), with the bottom lined with baking (parchment) paper, and press flat. If the mixture is sticky, keep your fingers dusted with flour.
2 Bake for 15 minutes, then remove from oven. While the base is cooling, make the topping.
3 Tip the granulated sugar into the bowl of a food processor and pour in the eggs. Process for 1 minute. Transfer the mixture to a bowl, then sprinkle the flour and baking powder over, and add lemon zest and juice. Mix together with a large spoon.
4 Pour the mixture on top of the base (it will fill the tin), then return it to the oven and bake for a further 30-35 minutes, or until golden in colour and firmish to the touch. Cool in the tin, then dust with icing sugar and cut into squares. Transfer to an airtight container when cool.
This super-delectable, sweet-but-tart ‘slice’ is quickly made in a food processor. If you don’t have a food processor, cream the butter and icing sugar and work in the flour. For the topping, whip the sugar and eggs together with a rotary beater. See Ilaria’s story on Sticky Lemon Slice