Instructions

1. Zest and juice the lemons. Measure 90ml of the juice and place into a bowl with half the zest, the sugar and butter. Beat the eggs and yolks together and stir into the other ingredients.
2. Place the bowl over a pan of gently simmering water, ensuring the bottom of the bowl is not in contact with the water. Cook the curd, stirring from time to time, until it is thick and holds a ribbon. This will take about 10 minutes. Strain through a sieve into a clean bowl and stir in the remaining lemon zest.
3. Cover the surface of the curd with cling film and leave to cool before transferring to the fridge to set. Any leftover curd can be stored in the fridge for up to 2 weeks.