Heat the oven to 160°C (fan). Line a 2lb loaf tin with greaseproof paper.
Beat the butter, olive oil and sugar together until pale and creamy.
Add the eggs in and mix well.
Sift in the flour, add the lemon zest and juice, then fold together until smooth.
Spoon into the tin, level it off, then bake for 1 hour until a skewer comes out clean.
Mix the lemon juice, zest and caster sugar for the drizzle.
As soon as the cake comes out, prick it all over with a fork, then pour over the drizzle. Let it soak in.
Leave to cool down in the tin for 15 minutes, then lift it out and leave it to cool completely on a cooling rack. Lift it out and slice it into portions. I served mine with a dollop of Greek yoghurt and some berries.