The sweetest Christmas: Lemon poppy seed squares

I have long adored poppy seed cakes with their delicate and sophisticated bitterness that goes so well with lemon.

MAKES 16 SQUARES

FOR THE CAKE

170g unsalted butter, cubed, plus extra for greasing

170g golden caster sugar

finely grated zest of 1 lemon, plus 2 tbsp lemon juice

3 medium eggs

170g self-raising flour, sifted

1 heaped tsp baking powder, sifted

30g poppy seeds

FOR THE TOPPING

50g unsalted butter

2 tbsp lemon juice

200g icing sugar, sifted

poppy seeds for scattering

• Preheat the oven to 190C/ 170C fan/gas 5 and grease a 23cm x 23cm square baking tin. For the cake, cream the butter and sugar with the lemon zest in a food processor, add the eggs one at a time, then the flour and baking powder. Add the lemon juice and whiz until creamy and, finally, pulse in the poppy seeds.
• Transfer the mixture to the tin, smoothing the surface, and bake for 30 minutes or until golden and firm when pressed. Run a knife around the edge of the cake then leave it to cool.
• For the icing, gently melt the butter, lemon juice and icing sugar in a small saucepan, whisking until smooth. Spread this over the top of the cake in a thin layer (you may not need quite all of it) and straightaway scatter with a few poppy seeds. Set aside for 30 minutes to set before cutting into squares. It will keep well for several days loosely covered.