Lemon Tarts made with Lemon Curd

The scenes in Downton Abbey episodes spend a lot of time drinking tea and eating little cakes, scones and biscuits.  On season 5 episode 2 I noticed they often spread sauce or curd on the breads.  Many years ago a very sweet English lady I worked with made Lemon Curd that she gave in jars as gifts.  Since then I have thought fondly about it and wished I had asked for her recipe.