Meyer Lemon Curd Recipe

I have a really simple lemon curd recipe that I've made for years, using whole eggs. This lemon curd recipe uses only the egg yolk, and the whites are reserved for making meringue for Lemon Meringue Tarts (or pie). My preferred lemons are Meyer but Eureka lemons work well, too. Lemon curd can be made up to a week ahead of time, and stores well in the refrigerator in a tightly sealed container (I use a sterile canning jar). Recipe comes from Martha Stewart.