Grapefruit Curd

• 1 large or 2 medium grapefruits with good skins
• 8 free-range egg yolks or 4

Grate the zest and squeeze the juice from the grapefruits, and put juice and zest in a double saucepan. Add the lightly beaten eggs, butter and sugar. Stir until the sugar has dissolved. Continue cooking and stirring until the mixture thickens, about 30 minutes.

Either use as described above in the introduction to this recipe or, for presents, pot in small, clean, dry jars, which you ha